WEBVTT 00:00.000 --> 00:01.000 align:start position:10% line:84.66% size:5% cc 00:01.000 --> 00:03.233 align:start position:10% line:84.66% size:7.5% ♪ ♪ 00:17.633 --> 00:19.133 align:start position:10% line:84.66% size:60% >> It is now my distinct 00:19.133 --> 00:20.666 align:start position:10% line:84.66% size:62.5% privilege and pleasure to 00:20.666 --> 00:22.766 align:start position:10% line:84.66% size:72.5% introduce to you your king of 00:22.766 --> 00:25.500 align:start position:10% line:84.66% size:80% Sprottania on Mars, from on high 00:25.500 --> 00:28.833 align:start position:10% line:84.66% size:70% on Mount Olympus, King Peter 00:28.833 --> 00:30.500 align:start position:10% line:84.66% size:15% Weixx! 00:30.500 --> 00:32.600 align:start position:10% line:84.66% size:25% [applause] 00:36.666 --> 00:37.933 align:start position:10% line:84.66% size:60% >> Good afternoon fellow 00:37.933 --> 00:39.733 align:start position:10% line:84.66% size:32.5% Sprottanians. 00:39.733 --> 00:41.000 align:start position:10% line:84.66% size:72.5% I'm so glad you could join us 00:41.000 --> 00:42.266 align:start position:10% line:84.66% size:72.5% here today for this wonderful 00:42.266 --> 00:43.933 align:start position:10% line:84.66% size:15% event. 00:43.933 --> 00:46.100 align:start position:10% line:84.66% size:80% Normally we are at home watching 00:46.100 --> 00:48.433 align:start position:10% line:84.66% size:72.5% television and The Wonders of 00:48.433 --> 00:50.066 align:start position:10% line:84.66% size:75% Physics show beamed to us from 00:50.066 --> 00:51.266 align:start position:10% line:84.66% size:15% Earth. 00:51.266 --> 00:52.566 align:start position:10% line:84.66% size:72.5% But I have a surprise for you 00:52.566 --> 00:53.933 align:start position:10% line:84.66% size:15% today. 00:53.933 --> 00:56.300 align:start position:10% line:84.66% size:77.5% I have invited Professor Sprott 00:56.300 --> 00:58.266 align:start position:10% line:84.66% size:72.5% to come to Mars and visit us, 00:58.266 --> 00:59.566 align:start position:10% line:84.66% size:57.5% and show us some of his 00:59.566 --> 01:01.600 align:start position:10% line:84.66% size:62.5% wonderful demonstrations. 01:01.600 --> 01:02.866 align:start position:10% line:84.66% size:72.5% If you look up in the sky you 01:02.866 --> 01:05.533 align:start position:10% line:84.66% size:70% can see him approaching now! 01:05.533 --> 01:07.433 align:start position:10% line:84.66% size:27.5% [whistling] 01:07.433 --> 01:09.666 align:start position:10% line:84.66% size:22.5% [laugher] 01:19.200 --> 01:22.633 align:start position:10% line:84.66% size:7.5% ♪ ♪ 01:22.633 --> 01:25.700 align:start position:10% line:84.66% size:57.5% [compresses air spurts] 01:25.700 --> 01:28.466 align:start position:10% line:84.66% size:25% [applause] 01:33.500 --> 01:34.900 align:start position:10% line:84.66% size:70% >> Welcome to The Wonders of 01:34.900 --> 01:36.033 align:start position:10% line:84.66% size:20% Physics. 01:36.033 --> 01:37.066 align:start position:10% line:84.66% size:67.5% Now we've taken our show to 01:37.066 --> 01:39.266 align:start position:10% line:84.66% size:72.5% Portugal, Egypt, South Africa 01:39.266 --> 01:41.200 align:start position:10% line:84.66% size:77.5% and Japan, but this is the very 01:41.200 --> 01:42.433 align:start position:10% line:84.66% size:70% first time I've ever been to 01:42.433 --> 01:44.100 align:start position:10% line:84.66% size:12.5% Mars. 01:44.100 --> 01:45.400 align:start position:10% line:84.66% size:75% It's a great pleasure to spend 01:45.400 --> 01:47.400 align:start position:10% line:84.66% size:72.5% our 30th season with you here 01:47.400 --> 01:48.466 align:start position:10% line:84.66% size:15% today. 01:48.466 --> 01:49.833 align:start position:10% line:84.66% size:70% Thank you for preparing this 01:49.833 --> 01:51.933 align:start position:10% line:84.66% size:72.5% atmosphere that I can breath. 01:51.933 --> 01:53.066 align:start position:10% line:84.66% size:72.5% I see you've prepared some of 01:53.066 --> 01:54.100 align:start position:10% line:84.66% size:57.5% the demonstrations that 01:54.100 --> 01:55.300 align:start position:10% line:84.66% size:25% requested. 01:55.300 --> 01:57.433 align:start position:10% line:84.66% size:80% >> Yes, welcome Professor Sprott 01:57.433 --> 01:59.066 align:start position:10% line:84.66% size:35% to Sprottania! 01:59.066 --> 02:00.500 align:start position:10% line:84.66% size:75% As you know, we have named our 02:00.500 --> 02:02.400 align:start position:10% line:84.66% size:37.5% city after you. 02:02.400 --> 02:03.766 align:start position:10% line:84.66% size:75% In over 30 years you have told 02:03.766 --> 02:05.933 align:start position:10% line:84.66% size:75% us that there are six areas of 02:05.933 --> 02:07.400 align:start position:10% line:84.66% size:45% classical physics. 02:07.400 --> 02:09.133 align:start position:10% line:84.66% size:65% It took you quite a bit of 02:09.133 --> 02:11.266 align:start position:10% line:84.66% size:72.5% motion to get here today, and 02:11.266 --> 02:13.400 align:start position:10% line:84.66% size:77.5% maybe there's a favorite motion 02:13.400 --> 02:14.466 align:start position:10% line:84.66% size:70% demonstration that you could 02:14.466 --> 02:15.700 align:start position:10% line:84.66% size:35% show us today. 02:15.700 --> 02:16.966 align:start position:10% line:84.66% size:67.5% >> Well, you know, asking a 02:16.966 --> 02:18.066 align:start position:10% line:84.66% size:65% physicist for his favorite 02:18.066 --> 02:19.433 align:start position:10% line:84.66% size:75% demonstration is a little like 02:19.433 --> 02:20.533 align:start position:10% line:84.66% size:72.5% asking a child which is their 02:20.533 --> 02:22.533 align:start position:10% line:84.66% size:40% favorite parent. 02:22.533 --> 02:23.766 align:start position:10% line:84.66% size:40% I like them all. 02:23.766 --> 02:25.000 align:start position:10% line:84.66% size:70% But there's one that is very 02:25.000 --> 02:26.866 align:start position:10% line:84.66% size:55% popular back on Earth. 02:26.866 --> 02:28.033 align:start position:10% line:84.66% size:70% If one of you Martians would 02:28.033 --> 02:29.233 align:start position:10% line:84.66% size:72.5% help me, I can demonstrate it 02:29.233 --> 02:31.233 align:start position:10% line:84.66% size:20% for you. 02:32.500 --> 02:34.733 align:start position:10% line:84.66% size:52.5% Okay, come down here. 02:37.066 --> 02:38.133 align:start position:10% line:84.66% size:70% Turn around and tell us your 02:38.133 --> 02:39.233 align:start position:10% line:84.66% size:12.5% name. 02:39.233 --> 02:40.300 align:start position:10% line:84.66% size:22.5% >> Damon. 02:40.300 --> 02:41.333 align:start position:10% line:84.66% size:22.5% >> Damon. 02:41.333 --> 02:42.533 align:start position:10% line:84.66% size:67.5% That's a good Martian name, 02:42.533 --> 02:43.566 align:start position:10% line:84.66% size:15% Damon. 02:43.566 --> 02:44.700 align:start position:10% line:84.66% size:75% Now Damon, I know on Mars they 02:44.700 --> 02:45.700 align:start position:10% line:84.66% size:30% have sports. 02:45.700 --> 02:46.700 align:start position:10% line:84.66% size:57.5% Are you good at sports? 02:46.700 --> 02:47.700 align:start position:10% line:84.66% size:25% >> Uh-huh. 02:47.700 --> 02:48.833 align:start position:10% line:84.66% size:32.5% >> Oh, great! 02:48.833 --> 02:49.866 align:start position:10% line:84.66% size:67.5% Have you ever gone bowling, 02:49.866 --> 02:50.900 align:start position:10% line:84.66% size:15% Damon? 02:50.900 --> 02:52.033 align:start position:10% line:84.66% size:17.5% >> Yes. 02:52.033 --> 02:53.100 align:start position:10% line:84.66% size:75% >> Bowling? Do you know sport? 02:53.100 --> 02:54.133 align:start position:10% line:84.66% size:77.5% We're going to take you bowling 02:54.133 --> 02:55.300 align:start position:10% line:84.66% size:32.5% today, Damon. 02:55.300 --> 02:56.400 align:start position:10% line:84.66% size:75% Turn to your right and go over 02:56.400 --> 02:57.466 align:start position:10% line:84.66% size:35% to King Weixx. 02:57.466 --> 02:58.533 align:start position:10% line:84.66% size:80% We're going to make what we call 02:58.533 --> 03:00.333 align:start position:10% line:84.66% size:60% a bowling ball pendulum. 03:00.333 --> 03:01.466 align:start position:10% line:84.66% size:77.5% A bowling ball is a heavy ball, 03:01.466 --> 03:02.566 align:start position:10% line:84.66% size:77.5% and the end of a wire suspended 03:02.566 --> 03:04.000 align:start position:10% line:84.66% size:42.5% from the ceiling. 03:04.000 --> 03:05.266 align:start position:10% line:84.66% size:72.5% Now on Earth the bowling ball 03:05.266 --> 03:06.533 align:start position:10% line:84.66% size:62.5% like this weighs about 16 03:06.533 --> 03:07.666 align:start position:10% line:84.66% size:17.5% pounds. 03:07.666 --> 03:08.866 align:start position:10% line:84.66% size:75% Here on Mars it's only about 6 03:08.866 --> 03:11.800 align:start position:10% line:84.66% size:70% pounds, but it's very heavy. 03:11.800 --> 03:13.333 align:start position:10% line:84.66% size:62.5% We want you to-- Oh, boy. 03:13.333 --> 03:15.166 align:start position:10% line:84.66% size:77.5% We're going to have to help you 03:15.166 --> 03:16.500 align:start position:10% line:84.66% size:32.5% a little bit. 03:16.500 --> 03:17.833 align:start position:10% line:84.66% size:72.5% We're going to hold this, and 03:17.833 --> 03:19.366 align:start position:10% line:84.66% size:80% when I say I want you to let go, 03:19.366 --> 03:20.366 align:start position:10% line:84.66% size:47.5% and then put your-- 03:20.366 --> 03:21.366 align:start position:10% line:84.66% size:35% Are you ready? 03:21.366 --> 03:22.733 align:start position:10% line:84.66% size:25% >> Uh-huh. 03:22.733 --> 03:23.866 align:start position:10% line:84.66% size:50% >> Okay, no, let go! 03:23.866 --> 03:25.633 align:start position:10% line:84.66% size:67.5% Put your hands down by your 03:25.633 --> 03:27.933 align:start position:10% line:84.66% size:52.5% side, and don't move. 03:27.933 --> 03:29.933 align:start position:10% line:84.66% size:42.5% Thank you, Damon! 03:29.933 --> 03:31.933 align:start position:10% line:84.66% size:25% [applause] 03:36.000 --> 03:37.033 align:start position:10% line:84.66% size:62.5% You know, when we do that 03:37.033 --> 03:38.233 align:start position:10% line:84.66% size:70% experiment back on Earth the 03:38.233 --> 03:39.466 align:start position:10% line:84.66% size:77.5% bowling ball goes out and comes 03:39.466 --> 03:41.466 align:start position:10% line:84.66% size:75% back about 60% faster, because 03:41.466 --> 03:42.933 align:start position:10% line:84.66% size:75% we have almost three times the 03:42.933 --> 03:44.600 align:start position:10% line:84.66% size:75% gravity on Earth that you have 03:44.600 --> 03:46.566 align:start position:10% line:84.66% size:32.5% here on Mars. 03:46.566 --> 03:48.400 align:start position:10% line:84.66% size:70% I've been enjoying this Mars 03:48.400 --> 03:50.233 align:start position:10% line:84.66% size:50% gravity quite a bit. 03:50.233 --> 03:52.066 align:start position:10% line:84.66% size:72.5% I feel very light on my feet. 03:52.066 --> 03:53.166 align:start position:10% line:84.66% size:75% I was wondering how high could 03:53.166 --> 03:54.600 align:start position:10% line:84.66% size:57.5% jump here with my Earth 03:54.600 --> 03:55.833 align:start position:10% line:84.66% size:20% muscles. 03:55.833 --> 03:57.900 align:start position:10% line:84.66% size:77.5% To keep me from injuring myself 03:57.900 --> 03:59.033 align:start position:10% line:84.66% size:75% I'm going to ask King Weixx to 03:59.033 --> 04:02.833 align:start position:10% line:84.66% size:50% attach a rope to me. 04:02.833 --> 04:04.066 align:start position:10% line:84.66% size:72.5% Then I'll just see how high I 04:04.066 --> 04:05.366 align:start position:10% line:84.66% size:22.5% can jump. 04:05.366 --> 04:07.000 align:start position:10% line:84.66% size:75% Let me scooch down and see how 04:07.000 --> 04:09.266 align:start position:10% line:84.66% size:35% high I can go! 04:09.266 --> 04:13.466 align:start position:10% line:84.66% size:25% [applause] 04:13.466 --> 04:19.000 align:start position:10% line:84.66% size:70% Do you want to see it again? 04:19.000 --> 04:23.100 align:start position:10% line:84.66% size:25% [applause] 04:23.100 --> 04:24.266 align:start position:10% line:84.66% size:70% >> Well, Professor Sprott, I 04:24.266 --> 04:25.366 align:start position:10% line:84.66% size:62.5% see you've discovered how 04:25.366 --> 04:26.466 align:start position:10% line:84.66% size:80% weightless you feel here on here 04:26.466 --> 04:27.566 align:start position:10% line:84.66% size:20% on Mars. 04:27.566 --> 04:28.866 align:start position:10% line:84.66% size:75% And indeed our gravity is much 04:28.866 --> 04:30.900 align:start position:10% line:84.66% size:60% less than that of Earth. 04:30.900 --> 04:32.466 align:start position:10% line:84.66% size:67.5% We have a physicist who has 04:32.466 --> 04:33.766 align:start position:10% line:84.66% size:75% been studying motion, and he'd 04:33.766 --> 04:34.900 align:start position:10% line:84.66% size:72.5% like to come out and show you 04:34.900 --> 04:36.300 align:start position:10% line:84.66% size:52.5% some of his findings. 04:36.300 --> 04:39.633 align:start position:10% line:84.66% size:62.5% I present to you, Mr. Ed! 04:39.633 --> 04:41.366 align:start position:10% line:84.66% size:35% >> Hehehehehe. 04:41.366 --> 04:44.000 align:start position:10% line:84.66% size:25% [applause] 04:44.000 --> 04:46.100 align:start position:10% line:84.66% size:70% What was that noise that you 04:46.100 --> 04:47.166 align:start position:10% line:84.66% size:12.5% made? 04:47.166 --> 04:48.433 align:start position:10% line:84.66% size:80% >> Oh, that's an old Earth joke. 04:48.433 --> 04:49.500 align:start position:10% line:84.66% size:42.5% Pay no attention. 04:49.500 --> 04:50.666 align:start position:10% line:84.66% size:77.5% >> I've got to, it sounded like 04:50.666 --> 04:51.866 align:start position:10% line:84.66% size:27.5% Morse code. 04:51.866 --> 04:52.866 align:start position:10% line:84.66% size:15% >> No. 04:52.866 --> 04:53.900 align:start position:10% line:84.66% size:70% >> Never heard of Morse code 04:53.900 --> 04:55.100 align:start position:10% line:84.66% size:17.5% before? 04:55.100 --> 04:56.300 align:start position:10% line:84.66% size:40% Mars horse code? 04:56.300 --> 04:57.466 align:start position:10% line:84.66% size:30% >> Oh, yeah. 04:57.466 --> 04:58.566 align:start position:10% line:84.66% size:25% [laughter] 04:58.566 --> 04:59.866 align:start position:10% line:84.66% size:20% >> Okay. 04:59.866 --> 05:00.966 align:start position:10% line:84.66% size:77.5% Anyway, motion is a pretty cool 05:00.966 --> 05:02.066 align:start position:10% line:84.66% size:80% thing, and they thought that I'd 05:02.066 --> 05:03.133 align:start position:10% line:84.66% size:70% like to meet you, Dr.Sprott, 05:03.133 --> 05:04.166 align:start position:10% line:84.66% size:45% because I've heard 05:04.166 --> 05:05.166 align:start position:10% line:84.66% size:72.5% you're quite the avid dancer. 05:05.166 --> 05:06.366 align:start position:10% line:84.66% size:47.5% >> I love to dance! 05:06.366 --> 05:07.533 align:start position:10% line:84.66% size:65% >> I also have some things 05:07.533 --> 05:09.500 align:start position:10% line:84.66% size:37.5% I'm working on. 05:09.500 --> 05:12.166 align:start position:10% line:84.66% size:70% The late Earth king, who you 05:12.166 --> 05:13.800 align:start position:10% line:84.66% size:75% might recall, I think his name 05:13.800 --> 05:14.900 align:start position:10% line:84.66% size:45% was Elvis Presley. 05:14.900 --> 05:15.966 align:start position:10% line:84.66% size:50% He is my mentor now. 05:15.966 --> 05:17.100 align:start position:10% line:84.66% size:75% He moved here in the late 70s. 05:17.100 --> 05:18.200 align:start position:10% line:84.66% size:25% [laughter] 05:18.200 --> 05:19.366 align:start position:10% line:84.66% size:17.5% >> Hum. 05:19.366 --> 05:20.533 align:start position:10% line:84.66% size:57.5% >> He's a great fellow. 05:20.533 --> 05:21.733 align:start position:10% line:84.66% size:80% Anyway, dancing is a really cool 05:21.733 --> 05:22.833 align:start position:10% line:84.66% size:72.5% motion, but so are some other 05:22.833 --> 05:24.000 align:start position:10% line:84.66% size:80% ones that are a little more easy 05:24.000 --> 05:25.100 align:start position:10% line:84.66% size:35% to talk about. 05:25.100 --> 05:26.166 align:start position:10% line:84.66% size:70% The first one I want to talk 05:26.166 --> 05:27.233 align:start position:10% line:84.66% size:75% about is straight-line motion. 05:27.233 --> 05:28.366 align:start position:10% line:84.66% size:72.5% In my hand here I have a tube 05:28.366 --> 05:29.600 align:start position:10% line:84.66% size:60% that I had open outside. 05:29.600 --> 05:30.800 align:start position:10% line:84.66% size:55% Outside is the Martian 05:30.800 --> 05:32.700 align:start position:10% line:84.66% size:80% atmosphere, which is about 1% as 05:32.700 --> 05:34.600 align:start position:10% line:84.66% size:80% dense as Earth atmosphere, which 05:34.600 --> 05:36.433 align:start position:10% line:84.66% size:40% is in this room. 05:36.433 --> 05:37.466 align:start position:10% line:84.66% size:70% Now on Earth they have these 05:37.466 --> 05:38.500 align:start position:10% line:84.66% size:80% things called pennies and cotton 05:38.500 --> 05:39.533 align:start position:10% line:84.66% size:15% balls. 05:39.533 --> 05:40.566 align:start position:10% line:84.66% size:70% I've got one of each in this 05:40.566 --> 05:41.866 align:start position:10% line:84.66% size:12.5% tube. 05:41.866 --> 05:42.933 align:start position:10% line:84.66% size:67.5% That was thanks to NASA and 05:42.933 --> 05:44.733 align:start position:10% line:84.66% size:25% Curiosity. 05:44.733 --> 05:45.933 align:start position:10% line:84.66% size:75% With only 1% the amount of air 05:45.933 --> 05:47.500 align:start position:10% line:84.66% size:77.5% in here, when I flip this tube, 05:47.500 --> 05:49.766 align:start position:10% line:84.66% size:70% you see that the two fall at 05:49.766 --> 05:51.666 align:start position:10% line:84.66% size:52.5% about the same speed. 05:51.666 --> 05:53.700 align:start position:10% line:84.66% size:77.5% I'll do it again the other way. 05:53.700 --> 05:54.800 align:start position:10% line:84.66% size:80% They fall and hit about the same 05:54.800 --> 05:56.133 align:start position:10% line:84.66% size:12.5% time. 05:56.133 --> 05:57.400 align:start position:10% line:84.66% size:72.5% Now when I open the valve and 05:57.400 --> 05:58.566 align:start position:10% line:84.66% size:72.5% allow the Earth atmosphere to 05:58.566 --> 06:00.933 align:start position:10% line:84.66% size:40% enter the tube-- 06:00.933 --> 06:02.066 align:start position:10% line:84.66% size:67.5% You can see the cotton ball 06:02.066 --> 06:04.233 align:start position:10% line:84.66% size:37.5% dance a little. 06:04.233 --> 06:05.533 align:start position:10% line:84.66% size:77.5% And when I make the race again, 06:05.533 --> 06:07.466 align:start position:10% line:84.66% size:80% The penny wins by at least three 06:07.466 --> 06:09.800 align:start position:10% line:84.66% size:60% or four times the speed. 06:09.800 --> 06:12.600 align:start position:10% line:84.66% size:25% [applause] 06:15.700 --> 06:17.466 align:start position:10% line:84.66% size:72.5% Now straight-line motion is a 06:17.466 --> 06:19.966 align:start position:10% line:84.66% size:75% lot of fun, but as a dancer, I 06:19.966 --> 06:21.166 align:start position:10% line:84.66% size:77.5% have to be well practiced in my 06:21.166 --> 06:22.633 align:start position:10% line:84.66% size:45% rotational motion. 06:22.633 --> 06:23.633 align:start position:10% line:84.66% size:75% I've got to spin every now and 06:23.633 --> 06:24.666 align:start position:10% line:84.66% size:12.5% then. 06:24.666 --> 06:26.200 align:start position:10% line:84.66% size:60% I'm still working on it. 06:26.200 --> 06:28.433 align:start position:10% line:84.66% size:60% Here I have a rotational 06:28.433 --> 06:29.700 align:start position:10% line:84.66% size:50% platform of science. 06:29.700 --> 06:32.333 align:start position:10% line:84.66% size:67.5% I'm going to stand on this. 06:32.333 --> 06:35.133 align:start position:10% line:84.66% size:77.5% There's a famous Earthling that 06:35.133 --> 06:36.466 align:start position:10% line:84.66% size:60% you might have heard of. 06:36.466 --> 06:38.000 align:start position:10% line:84.66% size:62.5% His name is Isaac Newton. 06:38.000 --> 06:39.233 align:start position:10% line:84.66% size:77.5% Isaac Newton came up with three 06:39.233 --> 06:41.533 align:start position:10% line:84.66% size:55% laws to govern motion. 06:41.533 --> 06:42.966 align:start position:10% line:84.66% size:77.5% The first one says as long as I 06:42.966 --> 06:45.333 align:start position:10% line:84.66% size:57.5% don't push something or 06:45.333 --> 06:46.766 align:start position:10% line:84.66% size:72.5% something pushes me, I'll sit 06:46.766 --> 06:49.000 align:start position:10% line:84.66% size:75% still or I won't start moving. 06:49.000 --> 06:50.700 align:start position:10% line:84.66% size:45% But that's boring. 06:50.700 --> 06:52.366 align:start position:10% line:84.66% size:70% I can stand here and just do 06:52.366 --> 06:53.566 align:start position:10% line:84.66% size:72.5% nothing, or do something more 06:53.566 --> 06:54.866 align:start position:10% line:84.66% size:22.5% exciting. 06:54.866 --> 06:56.266 align:start position:10% line:84.66% size:67.5% Now, his second law says if 06:56.266 --> 06:57.433 align:start position:10% line:84.66% size:77.5% something pushes me, I'll start 06:57.433 --> 06:59.166 align:start position:10% line:84.66% size:20% to move. 06:59.166 --> 07:00.800 align:start position:10% line:84.66% size:67.5% Dr. Sprott, would you maybe 07:00.800 --> 07:02.233 align:start position:10% line:84.66% size:52.5% start my moving here? 07:02.233 --> 07:03.866 align:start position:10% line:84.66% size:20% >> Sure. 07:03.866 --> 07:05.700 align:start position:10% line:84.66% size:7.5% ♪ ♪ 07:08.666 --> 07:10.033 align:start position:10% line:84.66% size:72.5% >> Okay, so that was a lot of 07:10.033 --> 07:11.866 align:start position:10% line:84.66% size:75% moving and spinning and so on, 07:11.866 --> 07:13.433 align:start position:10% line:84.66% size:80% but I want to stop, 'cause I get 07:13.433 --> 07:15.633 align:start position:10% line:84.66% size:47.5% dizzy pretty quick. 07:15.633 --> 07:16.866 align:start position:10% line:84.66% size:67.5% What I'm going to do is use 07:16.866 --> 07:18.133 align:start position:10% line:84.66% size:80% Newton's Third law which says if 07:18.133 --> 07:19.500 align:start position:10% line:84.66% size:70% I push something one way, it 07:19.500 --> 07:21.533 align:start position:10% line:84.66% size:57.5% will push me the other. 07:21.533 --> 07:22.533 align:start position:10% line:84.66% size:70% I'll use this rocket to stop 07:22.533 --> 07:24.000 align:start position:10% line:84.66% size:17.5% myself. 07:24.000 --> 07:25.000 align:start position:10% line:84.66% size:40% It's pretty fun. 07:25.000 --> 07:26.833 align:start position:10% line:84.66% size:57.5% [compresses air spurts] 07:26.833 --> 07:29.133 align:start position:10% line:84.66% size:25% [applause] 07:33.433 --> 07:35.400 align:start position:10% line:84.66% size:65% Now, after such a dizzying 07:35.400 --> 07:37.000 align:start position:10% line:84.66% size:80% performance, I think it's better 07:37.000 --> 07:38.366 align:start position:10% line:84.66% size:75% to stick to something a little 07:38.366 --> 07:39.766 align:start position:10% line:84.66% size:47.5% simpler after that. 07:39.766 --> 07:41.066 align:start position:10% line:84.66% size:70% I've seen Earth magicians on 07:41.066 --> 07:42.400 align:start position:10% line:84.66% size:75% the television here for a long 07:42.400 --> 07:44.100 align:start position:10% line:84.66% size:75% time, and they have this thing 07:44.100 --> 07:45.166 align:start position:10% line:84.66% size:50% they call a 'trick'. 07:45.166 --> 07:46.633 align:start position:10% line:84.66% size:65% I think I can pull it off. 07:46.633 --> 07:47.766 align:start position:10% line:84.66% size:70% I have here a beaker of Mars 07:47.766 --> 07:48.800 align:start position:10% line:84.66% size:15% water. 07:48.800 --> 07:49.933 align:start position:10% line:84.66% size:57.5% Now this stuff is rare. 07:49.933 --> 07:50.933 align:start position:10% line:84.66% size:80% I don't want to spill any during 07:50.933 --> 07:52.066 align:start position:10% line:84.66% size:12.5% this. 07:52.066 --> 07:53.133 align:start position:10% line:84.66% size:45% I want to pull the 07:53.133 --> 07:54.133 align:start position:10% line:84.66% size:75% silk cloth out from underneath 07:54.133 --> 07:55.233 align:start position:10% line:84.66% size:7.5% it. 07:55.233 --> 07:56.266 align:start position:10% line:84.66% size:60% Okay, now shout out some 07:56.266 --> 07:57.266 align:start position:10% line:84.66% size:30% suggestions. 07:57.266 --> 07:58.333 align:start position:10% line:84.66% size:52.5% How should I do this? 07:58.333 --> 07:59.600 align:start position:10% line:84.66% size:40% >> Pull it down. 07:59.600 --> 08:00.833 align:start position:10% line:84.66% size:40% >> Pull it down. 08:00.833 --> 08:02.066 align:start position:10% line:84.66% size:20% >> Yeah. 08:02.066 --> 08:03.700 align:start position:10% line:84.66% size:67.5% >> The table is in the way. 08:03.700 --> 08:05.400 align:start position:10% line:84.66% size:32.5% Anybody else? 08:05.400 --> 08:07.200 align:start position:10% line:84.66% size:45% Just shout it out! 08:07.200 --> 08:08.300 align:start position:10% line:84.66% size:47.5% >> Downward motion. 08:08.300 --> 08:10.200 align:start position:10% line:84.66% size:47.5% >> Downward motion. 08:10.200 --> 08:11.200 align:start position:10% line:84.66% size:35% A lot of down. 08:11.200 --> 08:12.233 align:start position:10% line:84.66% size:72.5% All right, we're going to try 08:12.233 --> 08:14.066 align:start position:10% line:84.66% size:22.5% the down. 08:14.066 --> 08:15.766 align:start position:10% line:84.66% size:55% Here we go, all right? 08:15.766 --> 08:17.566 align:start position:10% line:84.66% size:65% >> Fast, fast, fast, fast. 08:17.566 --> 08:19.200 align:start position:10% line:84.66% size:20% >> Fast? 08:19.200 --> 08:21.033 align:start position:10% line:84.66% size:25% All right. 08:21.033 --> 08:23.066 align:start position:10% line:84.66% size:25% [applause] 08:25.533 --> 08:27.166 align:start position:10% line:84.66% size:75% All right, thank you Dr.Sprott 08:27.166 --> 08:28.233 align:start position:10% line:84.66% size:75% for coming to Mars, and I hope 08:28.233 --> 08:29.666 align:start position:10% line:84.66% size:80% you enjoy the rest of your stay. 08:29.666 --> 08:30.733 align:start position:10% line:84.66% size:67.5% I'm a judge for this year's 08:30.733 --> 08:31.900 align:start position:10% line:84.66% size:77.5% Dancing With The Martians, so I 08:31.900 --> 08:33.200 align:start position:10% line:84.66% size:37.5% have to be off. 08:33.200 --> 08:35.200 align:start position:10% line:84.66% size:25% [applause] 08:39.133 --> 08:40.366 align:start position:10% line:84.66% size:80% >> Well, I'm sure a lot of those 08:40.366 --> 08:41.666 align:start position:10% line:84.66% size:80% dancers are really going to heat 08:41.666 --> 08:43.133 align:start position:10% line:84.66% size:47.5% up the dance floor. 08:43.133 --> 08:44.366 align:start position:10% line:84.66% size:42.5% Speaking of heat. 08:44.366 --> 08:45.566 align:start position:10% line:84.66% size:80% You know, being the king, I have 08:45.566 --> 08:46.666 align:start position:10% line:84.66% size:72.5% to wear I have to wear all of 08:46.666 --> 08:48.166 align:start position:10% line:84.66% size:47.5% these kingly robes. 08:48.166 --> 08:49.266 align:start position:10% line:84.66% size:75% It gets quite warm wearing all 08:49.266 --> 08:50.366 align:start position:10% line:84.66% size:35% of this stuff. 08:50.366 --> 08:51.600 align:start position:10% line:84.66% size:57.5% Heat is another area of 08:51.600 --> 08:53.066 align:start position:10% line:84.66% size:45% classical physics. 08:53.066 --> 08:54.100 align:start position:10% line:84.66% size:75% Maybe you could show us one of 08:54.100 --> 08:55.100 align:start position:10% line:84.66% size:45% your favorite heat 08:55.100 --> 08:56.500 align:start position:10% line:84.66% size:37.5% demonstrations? 08:56.500 --> 08:57.733 align:start position:10% line:84.66% size:77.5% >> Well, heat is important, and 08:57.733 --> 08:58.833 align:start position:10% line:84.66% size:77.5% you know, I've been pretty cold 08:58.833 --> 09:00.133 align:start position:10% line:84.66% size:65% since I came here to Mars. 09:00.133 --> 09:01.966 align:start position:10% line:84.66% size:72.5% Back on Earth we're closer to 09:01.966 --> 09:03.366 align:start position:10% line:84.66% size:62.5% the sun, and it's warmer. 09:03.366 --> 09:04.600 align:start position:10% line:84.66% size:70% I want to show you something 09:04.600 --> 09:05.800 align:start position:10% line:84.66% size:70% that's colder than your very 09:05.800 --> 09:07.200 align:start position:10% line:84.66% size:70% coldest winter night here on 09:07.200 --> 09:08.733 align:start position:10% line:84.66% size:12.5% Mars. 09:08.733 --> 09:10.266 align:start position:10% line:84.66% size:70% I have it in this container. 09:10.266 --> 09:11.266 align:start position:10% line:84.66% size:35% It's a liquid. 09:11.266 --> 09:12.433 align:start position:10% line:84.66% size:67.5% If I pour it out it looks a 09:12.433 --> 09:13.933 align:start position:10% line:84.66% size:70% little like water, except it 09:13.933 --> 09:15.600 align:start position:10% line:84.66% size:60% doesn't make things wet. 09:15.600 --> 09:16.700 align:start position:10% line:84.66% size:72.5% When it comes in contact with 09:16.700 --> 09:17.966 align:start position:10% line:84.66% size:72.5% the table it evaporates right 09:17.966 --> 09:19.366 align:start position:10% line:84.66% size:12.5% away. 09:19.366 --> 09:20.366 align:start position:10% line:84.66% size:77.5% This is something we have a lot 09:20.366 --> 09:21.500 align:start position:10% line:84.66% size:30% of on Earth. 09:21.500 --> 09:22.700 align:start position:10% line:84.66% size:52.5% It's called nitrogen. 09:22.700 --> 09:24.133 align:start position:10% line:84.66% size:70% Most of the air we breath is 09:24.133 --> 09:25.633 align:start position:10% line:84.66% size:22.5% nitrogen. 09:25.633 --> 09:27.766 align:start position:10% line:84.66% size:77.5% When you cool nitrogen gas down 09:27.766 --> 09:29.200 align:start position:10% line:84.66% size:77.5% to a low enough temperature, it 09:29.200 --> 09:30.900 align:start position:10% line:84.66% size:42.5% becomes a liquid. 09:30.900 --> 09:32.500 align:start position:10% line:84.66% size:52.5% This is a liquid at a 09:32.500 --> 09:35.200 align:start position:10% line:84.66% size:80% temperature of 321 degrees below 09:35.200 --> 09:38.100 align:start position:10% line:84.66% size:77.5% zero Fahrenheit, or a 196 below 09:38.100 --> 09:40.366 align:start position:10% line:84.66% size:32.5% zero Celsius. 09:40.366 --> 09:41.433 align:start position:10% line:84.66% size:65% There are many interesting 09:41.433 --> 09:42.833 align:start position:10% line:84.66% size:62.5% things we can do with it. 09:42.833 --> 09:43.933 align:start position:10% line:84.66% size:70% One thing I want to do is to 09:43.933 --> 09:45.333 align:start position:10% line:84.66% size:72.5% take a little stainless steel 09:45.333 --> 09:46.533 align:start position:10% line:84.66% size:75% cup and lower it down into the 09:46.533 --> 09:48.300 align:start position:10% line:84.66% size:40% liquid nitrogen. 09:48.300 --> 09:50.566 align:start position:10% line:84.66% size:77.5% It causes the nitrogen to boil. 09:50.566 --> 09:51.833 align:start position:10% line:84.66% size:80% That's because the cup is at the 09:51.833 --> 09:53.766 align:start position:10% line:84.66% size:75% temperature of the room, so it 09:53.766 --> 09:55.266 align:start position:10% line:84.66% size:75% is much warmer than the liquid 09:55.266 --> 09:56.533 align:start position:10% line:84.66% size:22.5% nitrogen. 09:56.533 --> 09:57.600 align:start position:10% line:84.66% size:77.5% It heats it up and causes it to 09:57.600 --> 09:59.166 align:start position:10% line:84.66% size:12.5% boil. 09:59.166 --> 10:01.133 align:start position:10% line:84.66% size:72.5% After a little while, the cup 10:01.133 --> 10:02.400 align:start position:10% line:84.66% size:75% will cool down to the very low 10:02.400 --> 10:04.533 align:start position:10% line:84.66% size:72.5% temperature of the liquid and 10:04.533 --> 10:06.666 align:start position:10% line:84.66% size:55% the boiling will stop. 10:06.666 --> 10:07.966 align:start position:10% line:84.66% size:77.5% Once that happens, I'm going to 10:07.966 --> 10:10.366 align:start position:10% line:84.66% size:80% be able to remove the cup and it 10:10.366 --> 10:11.733 align:start position:10% line:84.66% size:62.5% still has a little liquid 10:11.733 --> 10:13.166 align:start position:10% line:84.66% size:37.5% nitrogen in it. 10:13.166 --> 10:14.166 align:start position:10% line:84.66% size:80% I can shake it and spill it, but 10:14.166 --> 10:15.900 align:start position:10% line:84.66% size:77.5% I don't want to spill too much, 10:15.900 --> 10:17.100 align:start position:10% line:84.66% size:77.5% because I want to lower it down 10:17.100 --> 10:19.600 align:start position:10% line:84.66% size:80% into this brass cylinder, take a 10:19.600 --> 10:21.833 align:start position:10% line:84.66% size:60% cork and hammer it down. 10:25.400 --> 10:26.533 align:start position:10% line:84.66% size:72.5% Then I'll just take the whole 10:26.533 --> 10:28.866 align:start position:10% line:84.66% size:47.5% thing and shake it. 10:28.866 --> 10:30.500 align:start position:10% line:84.66% size:27.5% [cork pops] 10:30.500 --> 10:32.600 align:start position:10% line:84.66% size:67.5% [exclamations and applause] 10:43.233 --> 10:46.000 align:start position:10% line:84.66% size:65% >> Well that went off with 10:46.000 --> 10:48.500 align:start position:10% line:84.66% size:40% a bit of a bang! 10:48.500 --> 10:50.333 align:start position:10% line:84.66% size:77.5% If I heard correctly, Professor 10:50.333 --> 10:53.533 align:start position:10% line:84.66% size:75% Sprott was talking about heat. 10:53.533 --> 10:55.833 align:start position:10% line:84.66% size:67.5% I am the Martian Steward of 10:55.833 --> 10:58.566 align:start position:10% line:84.66% size:77.5% the Land, Wind and Water, and I 10:58.566 --> 11:00.600 align:start position:10% line:84.66% size:77.5% am all knowing when it comes to 11:00.600 --> 11:04.366 align:start position:10% line:84.66% size:77.5% things hot, cold or in between. 11:04.366 --> 11:05.433 align:start position:10% line:84.66% size:67.5% >> Well, now wait a minute, 11:05.433 --> 11:06.566 align:start position:10% line:84.66% size:80% land and wind I see lots of here 11:06.566 --> 11:08.233 align:start position:10% line:84.66% size:47.5% on Mars, but water? 11:08.233 --> 11:09.500 align:start position:10% line:84.66% size:70% There are no rivers or lakes 11:09.500 --> 11:11.133 align:start position:10% line:84.66% size:12.5% here. 11:11.133 --> 11:12.166 align:start position:10% line:84.66% size:72.5% >> Please, don't let the king 11:12.166 --> 11:13.400 align:start position:10% line:84.66% size:55% hear you mention that. 11:13.400 --> 11:15.200 align:start position:10% line:84.66% size:70% He is still very angry at my 11:15.200 --> 11:16.333 align:start position:10% line:84.66% size:72.5% predecessor for what happened 11:16.333 --> 11:18.500 align:start position:10% line:84.66% size:32.5% to the water. 11:18.500 --> 11:21.000 align:start position:10% line:84.66% size:70% Still, on Mars, we have some 11:21.000 --> 11:22.566 align:start position:10% line:84.66% size:40% princely things. 11:22.566 --> 11:24.400 align:start position:10% line:84.66% size:72.5% As every Martian child knows, 11:24.400 --> 11:26.400 align:start position:10% line:84.66% size:67.5% Mars has the solar system's 11:26.400 --> 11:28.566 align:start position:10% line:84.66% size:57.5% tallest known mountain. 11:28.566 --> 11:31.100 align:start position:10% line:84.66% size:72.5% It's an extinct volcano named 11:31.100 --> 11:32.533 align:start position:10% line:84.66% size:32.5% Olympus Mons. 11:32.533 --> 11:35.033 align:start position:10% line:84.66% size:72.5% It is three times taller than 11:35.033 --> 11:37.800 align:start position:10% line:84.66% size:67.5% Earth's puny Mount Everest, 11:37.800 --> 11:41.200 align:start position:10% line:84.66% size:67.5% thanks to our weak gravity. 11:41.200 --> 11:42.933 align:start position:10% line:84.66% size:67.5% Dear Professor Sprott, many 11:42.933 --> 11:45.366 align:start position:10% line:84.66% size:72.5% Martian children have enjoyed 11:45.366 --> 11:47.466 align:start position:10% line:84.66% size:72.5% your Wonders of Physics show. 11:47.466 --> 11:48.900 align:start position:10% line:84.66% size:65% Some have even braved this 11:48.900 --> 11:50.733 align:start position:10% line:84.66% size:57.5% thick, dense Earth-like 11:50.733 --> 11:52.800 align:start position:10% line:84.66% size:55% atmosphere to be here. 11:52.800 --> 11:54.933 align:start position:10% line:84.66% size:70% Some, I know, are quite shy. 11:54.933 --> 11:56.066 align:start position:10% line:84.66% size:70% I think I know where they're 11:56.066 --> 11:57.433 align:start position:10% line:84.66% size:17.5% hiding. 11:57.433 --> 11:58.633 align:start position:10% line:84.66% size:75% Come out, come out, where ever 11:58.633 --> 12:01.000 align:start position:10% line:84.66% size:20% you are! 12:01.000 --> 12:03.633 align:start position:10% line:84.66% size:47.5% Ah, there they are. 12:03.633 --> 12:05.200 align:start position:10% line:84.66% size:70% Come on, you want to see the 12:05.200 --> 12:09.033 align:start position:10% line:84.66% size:75% show just like everybody else. 12:09.033 --> 12:10.600 align:start position:10% line:84.66% size:35% Here they are. 12:10.600 --> 12:12.066 align:start position:10% line:84.66% size:67.5% We'll put them up, turn you 12:12.066 --> 12:13.433 align:start position:10% line:84.66% size:17.5% around. 12:13.433 --> 12:15.600 align:start position:10% line:84.66% size:52.5% This one's quite shy. 12:15.600 --> 12:16.966 align:start position:10% line:84.66% size:65% These children are budding 12:16.966 --> 12:18.166 align:start position:10% line:84.66% size:27.5% scientists. 12:18.166 --> 12:19.866 align:start position:10% line:84.66% size:67.5% They have been hard at work 12:19.866 --> 12:21.700 align:start position:10% line:84.66% size:57.5% collecting an odorless, 12:21.700 --> 12:23.600 align:start position:10% line:84.66% size:70% colorless gas named methane, 12:23.600 --> 12:25.533 align:start position:10% line:84.66% size:45% near Olympus Mons. 12:25.533 --> 12:27.200 align:start position:10% line:84.66% size:72.5% It is often seen near Earth's 12:27.200 --> 12:29.566 align:start position:10% line:84.66% size:25% volcanoes. 12:29.566 --> 12:32.133 align:start position:10% line:84.66% size:62.5% Because it's odorless and 12:32.133 --> 12:34.133 align:start position:10% line:84.66% size:80% colorless, you can't see it, you 12:34.133 --> 12:36.433 align:start position:10% line:84.66% size:72.5% can't taste it, but we have a 12:36.433 --> 12:38.766 align:start position:10% line:84.66% size:47.5% demonstration here. 12:38.766 --> 12:40.233 align:start position:10% line:84.66% size:67.5% There's a tank in the back. 12:40.233 --> 12:41.866 align:start position:10% line:84.66% size:72.5% We'll open the valve here and 12:41.866 --> 12:43.600 align:start position:10% line:84.66% size:80% bubble that methane through this 12:43.600 --> 12:46.333 align:start position:10% line:84.66% size:35% soap solution. 12:46.333 --> 12:48.833 align:start position:10% line:84.66% size:55% We'll see what we get. 12:50.933 --> 12:54.933 align:start position:10% line:84.66% size:62.5% Ohh, do you like bubbles? 12:54.933 --> 12:57.066 align:start position:10% line:84.66% size:80% Now let's see what these bubbles 12:57.066 --> 12:59.500 align:start position:10% line:84.66% size:7.5% do. 12:59.500 --> 13:00.833 align:start position:10% line:84.66% size:65% Let's see if it will work. 13:00.833 --> 13:01.933 align:start position:10% line:84.66% size:50% It's getting bigger. 13:01.933 --> 13:05.200 align:start position:10% line:84.66% size:62.5% We'll just help it along. 13:05.200 --> 13:07.866 align:start position:10% line:84.66% size:35% Oh, very nice. 13:07.866 --> 13:10.000 align:start position:10% line:84.66% size:77.5% Methane is less dense that this 13:10.000 --> 13:12.300 align:start position:10% line:84.66% size:77.5% Earth-like atmosphere and so it 13:12.300 --> 13:14.266 align:start position:10% line:84.66% size:17.5% floats. 13:14.266 --> 13:15.633 align:start position:10% line:84.66% size:67.5% There's another property of 13:15.633 --> 13:20.466 align:start position:10% line:84.66% size:80% methane that I want to show you. 13:20.466 --> 13:24.366 align:start position:10% line:84.66% size:75% I have to light my candle, but 13:24.366 --> 13:26.233 align:start position:10% line:84.66% size:77.5% I'll probably use the match for 13:26.233 --> 13:27.266 align:start position:10% line:84.66% size:12.5% this. 13:27.266 --> 13:29.166 align:start position:10% line:84.66% size:67.5% [exclamations and applause] 13:29.166 --> 13:31.133 align:start position:10% line:84.66% size:10% Yes. 13:34.633 --> 13:36.400 align:start position:10% line:84.66% size:70% In the presence of an oxygen 13:36.400 --> 13:38.933 align:start position:10% line:84.66% size:62.5% atmosphere methane burns. 13:38.933 --> 13:40.500 align:start position:10% line:84.66% size:62.5% Should we try that again? 13:40.500 --> 13:43.066 align:start position:10% line:84.66% size:32.5% >> all: Yeah! 13:43.066 --> 13:47.466 align:start position:10% line:84.66% size:55% >> Okay, let's try it. 13:47.466 --> 13:48.633 align:start position:10% line:84.66% size:32.5% Here it goes. 13:48.633 --> 13:51.900 align:start position:10% line:84.66% size:25% [applause] 13:55.866 --> 13:57.300 align:start position:10% line:84.66% size:80% Right now we'll do an experiment 13:57.300 --> 13:59.000 align:start position:10% line:84.66% size:55% that shows us what the 13:59.000 --> 14:01.000 align:start position:10% line:84.66% size:75% atmosphere in this room can do 14:01.000 --> 14:05.266 align:start position:10% line:84.66% size:80% if we allow the water vapor, the 14:05.266 --> 14:07.233 align:start position:10% line:84.66% size:77.5% steam inside this container, to 14:07.233 --> 14:09.833 align:start position:10% line:84.66% size:55% turn back into liquid. 14:09.833 --> 14:11.700 align:start position:10% line:84.66% size:80% We will turn off the heat, which 14:11.700 --> 14:12.966 align:start position:10% line:84.66% size:27.5% I just did. 14:12.966 --> 14:14.833 align:start position:10% line:84.66% size:80% We will seal this valve nice and 14:14.833 --> 14:16.200 align:start position:10% line:84.66% size:15% tight. 14:16.200 --> 14:17.833 align:start position:10% line:84.66% size:72.5% Then it's going to start cool 14:17.833 --> 14:19.333 align:start position:10% line:84.66% size:12.5% down. 14:19.333 --> 14:21.600 align:start position:10% line:84.66% size:72.5% That water vapor, that steam, 14:21.600 --> 14:24.766 align:start position:10% line:84.66% size:77.5% will condense back into liquid, 14:24.766 --> 14:29.900 align:start position:10% line:84.66% size:80% and when it does it will shrink. 14:29.900 --> 14:31.933 align:start position:10% line:84.66% size:80% It will shrink about a factor of 14:31.933 --> 14:35.600 align:start position:10% line:84.66% size:60% 2,000, leaving a vacuum. 14:35.600 --> 14:37.133 align:start position:10% line:84.66% size:67.5% Now you'll see what the air 14:37.133 --> 14:39.833 align:start position:10% line:84.66% size:80% pressure in this room will do to 14:39.833 --> 14:44.766 align:start position:10% line:84.66% size:47.5% this very hard can. 14:44.766 --> 14:46.833 align:start position:10% line:84.66% size:67.5% It takes a while sometimes. 14:53.500 --> 14:55.633 align:start position:10% line:84.66% size:30% There we go. 14:55.633 --> 15:00.433 align:start position:10% line:84.66% size:37.5% It's shrinking. 15:00.433 --> 15:02.400 align:start position:10% line:84.66% size:45% Ah, a little help. 15:02.400 --> 15:05.666 align:start position:10% line:84.66% size:25% [applause] 15:10.533 --> 15:12.900 align:start position:10% line:84.66% size:80% Now, you don't feel the pressure 15:12.900 --> 15:15.066 align:start position:10% line:84.66% size:77.5% from this Earth-like atmosphere 15:15.066 --> 15:17.000 align:start position:10% line:84.66% size:37.5% but it's there. 15:17.000 --> 15:18.633 align:start position:10% line:84.66% size:72.5% We have another demonstration 15:18.633 --> 15:20.600 align:start position:10% line:84.66% size:72.5% that allows us to compare the 15:20.600 --> 15:22.900 align:start position:10% line:84.66% size:70% Martian atmospheric pressure 15:22.900 --> 15:24.933 align:start position:10% line:84.66% size:65% with the Earth atmospheric 15:24.933 --> 15:26.233 align:start position:10% line:84.66% size:55% pressure, and that's a 15:26.233 --> 15:27.400 align:start position:10% line:84.66% size:77.5% demonstration over here in this 15:27.400 --> 15:28.966 align:start position:10% line:84.66% size:25% long tube. 15:28.966 --> 15:30.666 align:start position:10% line:84.66% size:50% But before I run the 15:30.666 --> 15:32.133 align:start position:10% line:84.66% size:70% demonstration, I will need a 15:32.133 --> 15:34.300 align:start position:10% line:84.66% size:75% volunteer from the audience to 15:34.300 --> 15:36.466 align:start position:10% line:84.66% size:72.5% help me out with this special 15:36.466 --> 15:38.966 align:start position:10% line:84.66% size:47.5% can of Martian Dew. 15:38.966 --> 15:41.200 align:start position:10% line:84.66% size:32.5% Martian, see? 15:41.200 --> 15:43.066 align:start position:10% line:84.66% size:70% Let's see, who will come up? 15:43.066 --> 15:46.333 align:start position:10% line:84.66% size:77.5% The boy in the fluorescent neon 15:46.333 --> 15:51.866 align:start position:10% line:84.66% size:50% green, come on down. 15:51.866 --> 15:54.100 align:start position:10% line:84.66% size:55% Are you really strong? 15:54.100 --> 15:55.266 align:start position:10% line:84.66% size:70% Do you think you could crush 15:55.266 --> 15:56.666 align:start position:10% line:84.66% size:22.5% this can? 15:56.666 --> 15:57.800 align:start position:10% line:84.66% size:32.5% >> Which way? 15:57.800 --> 15:58.800 align:start position:10% line:84.66% size:32.5% >> Which way. 15:58.800 --> 16:00.233 align:start position:10% line:84.66% size:70% What's your name by the way? 16:00.233 --> 16:01.333 align:start position:10% line:84.66% size:20% >> Kelan 16:01.333 --> 16:02.733 align:start position:10% line:84.66% size:72.5% >> Kelan, that's a nice name. 16:02.733 --> 16:03.933 align:start position:10% line:84.66% size:60% Which way, that's a good 16:03.933 --> 16:05.166 align:start position:10% line:84.66% size:22.5% question. 16:05.166 --> 16:06.733 align:start position:10% line:84.66% size:42.5% The first person. 16:06.733 --> 16:07.966 align:start position:10% line:84.66% size:55% With a ping-pong ball. 16:07.966 --> 16:11.033 align:start position:10% line:84.66% size:25% [laughter] 16:11.033 --> 16:13.033 align:start position:10% line:84.66% size:80% Stand over here, throw that ball 16:13.033 --> 16:14.900 align:start position:10% line:84.66% size:80% as hard as you can to crush that 16:14.900 --> 16:16.566 align:start position:10% line:84.66% size:10% can. 16:16.566 --> 16:19.900 align:start position:10% line:84.66% size:25% [laughter] 16:19.900 --> 16:21.600 align:start position:10% line:84.66% size:52.5% Thank you, try again. 16:21.600 --> 16:23.000 align:start position:10% line:84.66% size:80% You can get as close as you want 16:23.000 --> 16:24.566 align:start position:10% line:84.66% size:45% so you can hit it. 16:24.566 --> 16:26.066 align:start position:10% line:84.66% size:52.5% Let's get a good hit. 16:26.066 --> 16:27.266 align:start position:10% line:84.66% size:32.5% There you go! 16:27.266 --> 16:28.733 align:start position:10% line:84.66% size:42.5% Did you crush it? 16:28.733 --> 16:30.033 align:start position:10% line:84.66% size:40% >> A little bit. 16:30.033 --> 16:31.500 align:start position:10% line:84.66% size:77.5% >> A little bit, well, you made 16:31.500 --> 16:32.633 align:start position:10% line:84.66% size:32.5% a dent in it. 16:32.633 --> 16:34.500 align:start position:10% line:84.66% size:57.5% We'll try to do better. 16:34.500 --> 16:36.100 align:start position:10% line:84.66% size:50% Thank you very much. 16:36.100 --> 16:41.133 align:start position:10% line:84.66% size:25% [applause] 16:41.133 --> 16:42.566 align:start position:10% line:84.66% size:80% We will put this can back in the 16:42.566 --> 16:47.000 align:start position:10% line:84.66% size:35% little holder. 16:47.000 --> 16:48.533 align:start position:10% line:84.66% size:75% We have another ping-pong ball 16:48.533 --> 16:49.866 align:start position:10% line:84.66% size:27.5% right here. 16:49.866 --> 16:51.200 align:start position:10% line:84.66% size:62.5% Right now in the tube the 16:51.200 --> 16:52.466 align:start position:10% line:84.66% size:77.5% pressure's the same as it is in 16:52.466 --> 16:54.366 align:start position:10% line:84.66% size:80% the room, but when I ask, please 16:54.366 --> 16:55.900 align:start position:10% line:84.66% size:72.5% Professor Sprott, turn on the 16:55.900 --> 16:58.500 align:start position:10% line:84.66% size:80% pump, we are now pumping the air 16:58.500 --> 17:01.466 align:start position:10% line:84.66% size:40% out of the tube. 17:01.466 --> 17:03.366 align:start position:10% line:84.66% size:70% It has windows that hold the 17:03.366 --> 17:06.600 align:start position:10% line:84.66% size:35% vacuum inside. 17:06.600 --> 17:08.366 align:start position:10% line:84.66% size:55% I can watch this gage. 17:08.366 --> 17:10.100 align:start position:10% line:84.66% size:70% When it reaches the pressure 17:10.100 --> 17:12.400 align:start position:10% line:84.66% size:65% outside of our dome on the 17:12.400 --> 17:16.066 align:start position:10% line:84.66% size:70% surface of Mars, then we can 17:16.066 --> 17:18.400 align:start position:10% line:84.66% size:70% perform a second experiment. 17:18.400 --> 17:21.600 align:start position:10% line:84.66% size:72.5% We will remove the safety, we 17:21.600 --> 17:23.233 align:start position:10% line:84.66% size:77.5% will push this plunger, it will 17:23.233 --> 17:25.966 align:start position:10% line:84.66% size:75% break this plastic letting the 17:25.966 --> 17:28.766 align:start position:10% line:84.66% size:70% Earth-like atmosphere on one 17:28.766 --> 17:30.400 align:start position:10% line:84.66% size:55% side and the Mars-like 17:30.400 --> 17:31.833 align:start position:10% line:84.66% size:70% atmosphere on the other, and 17:31.833 --> 17:34.300 align:start position:10% line:84.66% size:80% that force from the air pressure 17:34.300 --> 17:35.566 align:start position:10% line:84.66% size:67.5% will speed up the ping-pong 17:35.566 --> 17:36.966 align:start position:10% line:84.66% size:12.5% ball. 17:36.966 --> 17:38.366 align:start position:10% line:84.66% size:47.5% We'll see how fast. 17:38.366 --> 17:39.500 align:start position:10% line:84.66% size:67.5% Good job holding your ears. 17:39.500 --> 17:40.600 align:start position:10% line:84.66% size:25% Very good. 17:40.600 --> 17:42.033 align:start position:10% line:84.66% size:57.5% I'll need a count-down. 17:42.033 --> 17:44.533 align:start position:10% line:84.66% size:40% Three, two, one. 17:44.533 --> 17:46.666 align:start position:10% line:84.66% size:37.5% [popping sound] 17:46.666 --> 17:49.433 align:start position:10% line:84.66% size:25% [applause] 17:55.233 --> 17:58.366 align:start position:10% line:84.66% size:57.5% We did a little better. 17:58.366 --> 18:01.266 align:start position:10% line:84.66% size:60% >> Well I'm crushed that 18:01.266 --> 18:05.366 align:start position:10% line:84.66% size:80% my time is up, Professor Sprott. 18:05.366 --> 18:07.800 align:start position:10% line:84.66% size:67.5% I have more work to do near 18:07.800 --> 18:10.000 align:start position:10% line:84.66% size:32.5% Olympus Mons. 18:10.000 --> 18:11.533 align:start position:10% line:84.66% size:70% It would appear there's some 18:11.533 --> 18:14.300 align:start position:10% line:84.66% size:77.5% rumbling sounds coming from it. 18:14.300 --> 18:15.633 align:start position:10% line:84.66% size:75% Maybe its not so extinct after 18:15.633 --> 18:17.900 align:start position:10% line:84.66% size:10% all. 18:17.900 --> 18:21.233 align:start position:10% line:84.66% size:25% [applause] 18:21.233 --> 18:23.166 align:start position:10% line:84.66% size:72.5% >> Well, Professor Sprott, he 18:23.166 --> 18:25.266 align:start position:10% line:84.66% size:60% sure was a noisy fellow. 18:25.266 --> 18:27.866 align:start position:10% line:84.66% size:77.5% I like things to be very quiet. 18:27.866 --> 18:29.500 align:start position:10% line:84.66% size:80% Here on Mars, since we have such 18:29.500 --> 18:31.666 align:start position:10% line:84.66% size:75% a thin atmosphere, sounds does 18:31.666 --> 18:33.566 align:start position:10% line:84.66% size:70% not travel very well at all. 18:33.566 --> 18:35.133 align:start position:10% line:84.66% size:75% When I'm outside playing golf, 18:35.133 --> 18:36.333 align:start position:10% line:84.66% size:50% it's nice and quiet. 18:36.333 --> 18:37.766 align:start position:10% line:84.66% size:75% I understand on Earth you have 18:37.766 --> 18:39.066 align:start position:10% line:84.66% size:67.5% a lot of birds that must be 18:39.066 --> 18:40.166 align:start position:10% line:84.66% size:80% really noisy when you're playing 18:40.166 --> 18:41.400 align:start position:10% line:84.66% size:12.5% golf. 18:41.400 --> 18:42.533 align:start position:10% line:84.66% size:80% So anyhow, sound is another area 18:42.533 --> 18:43.700 align:start position:10% line:84.66% size:52.5% of classical physics. 18:43.700 --> 18:44.933 align:start position:10% line:84.66% size:75% Maybe you could show us one of 18:44.933 --> 18:46.166 align:start position:10% line:84.66% size:47.5% your favorite sound 18:46.166 --> 18:47.233 align:start position:10% line:84.66% size:37.5% demonstrations. 18:47.233 --> 18:48.366 align:start position:10% line:84.66% size:60% >> You know, it is noisy 18:48.366 --> 18:49.466 align:start position:10% line:84.66% size:45% back on Earth, and 18:49.466 --> 18:50.633 align:start position:10% line:84.66% size:70% sometimes it bothers me too. 18:50.633 --> 18:52.233 align:start position:10% line:84.66% size:65% Not so much the birds, but 18:52.233 --> 18:53.300 align:start position:10% line:84.66% size:72.5% there's lots of noise that we 18:53.300 --> 18:54.466 align:start position:10% line:84.66% size:12.5% have. 18:54.466 --> 18:55.900 align:start position:10% line:84.66% size:72.5% Sound is kind of odd, because 18:55.900 --> 18:57.666 align:start position:10% line:84.66% size:42.5% you can't see it. 18:57.666 --> 18:59.166 align:start position:10% line:84.66% size:57.5% You can hear it, right? 18:59.166 --> 19:00.666 align:start position:10% line:84.66% size:70% Sound is a form of wave, and 19:00.666 --> 19:02.133 align:start position:10% line:84.66% size:80% there is a way for me to make it 19:02.133 --> 19:04.000 align:start position:10% line:84.66% size:67.5% obvious to you that it is a 19:04.000 --> 19:04.966 align:start position:10% line:84.66% size:12.5% wave. 19:04.966 --> 19:06.533 align:start position:10% line:84.66% size:72.5% I use this gadget right here. 19:06.533 --> 19:10.300 align:start position:10% line:84.66% size:80% Do you know what this is called? 19:10.300 --> 19:13.366 align:start position:10% line:84.66% size:75% That's right, an oscilloscope. 19:13.366 --> 19:14.866 align:start position:10% line:84.66% size:55% It's connected to this 19:14.866 --> 19:16.633 align:start position:10% line:84.66% size:75% microphone, so any sounds that 19:16.633 --> 19:17.866 align:start position:10% line:84.66% size:70% come into here are displayed 19:17.866 --> 19:19.066 align:start position:10% line:84.66% size:15% there. 19:19.066 --> 19:20.233 align:start position:10% line:84.66% size:72.5% You can see what a sound wave 19:20.233 --> 19:21.400 align:start position:10% line:84.66% size:80% would look like if you could see 19:21.400 --> 19:22.600 align:start position:10% line:84.66% size:7.5% it. 19:22.600 --> 19:24.000 align:start position:10% line:84.66% size:67.5% You see how complicated the 19:24.000 --> 19:25.066 align:start position:10% line:84.66% size:62.5% sound is corresponding to 19:25.066 --> 19:26.333 align:start position:10% line:84.66% size:17.5% speech. 19:26.333 --> 19:27.533 align:start position:10% line:84.66% size:75% Not all sounds are complicated 19:27.533 --> 19:28.633 align:start position:10% line:84.66% size:25% like that. 19:28.633 --> 19:30.766 align:start position:10% line:84.66% size:55% Do you recognize this? 19:30.766 --> 19:31.833 align:start position:10% line:84.66% size:12.5% What? 19:31.833 --> 19:33.100 align:start position:10% line:84.66% size:35% A tuning fork. 19:33.100 --> 19:34.266 align:start position:10% line:84.66% size:75% A U-shaped piece of metal, you 19:34.266 --> 19:35.433 align:start position:10% line:84.66% size:75% strike it with a mallet and it 19:35.433 --> 19:36.600 align:start position:10% line:84.66% size:35% makes a sound. 19:36.600 --> 19:37.666 align:start position:10% line:84.66% size:80% We're going to do it and look on 19:37.666 --> 19:38.833 align:start position:10% line:84.66% size:42.5% the oscilloscope. 19:38.833 --> 19:40.733 align:start position:10% line:84.66% size:15% [tone] 19:42.666 --> 19:43.900 align:start position:10% line:84.66% size:72.5% That's a very regular kind of 19:43.900 --> 19:45.266 align:start position:10% line:84.66% size:15% sound. 19:45.266 --> 19:47.033 align:start position:10% line:84.66% size:80% That's what we call a sine wave. 19:47.033 --> 19:49.200 align:start position:10% line:84.66% size:75% It's the purest type of sound. 19:49.200 --> 19:50.500 align:start position:10% line:84.66% size:57.5% It consists of a single 19:50.500 --> 19:51.866 align:start position:10% line:84.66% size:25% frequency. 19:51.866 --> 19:54.200 align:start position:10% line:84.66% size:80% In this case it's 440 cycles per 19:54.200 --> 19:55.500 align:start position:10% line:84.66% size:17.5% second. 19:55.500 --> 19:56.833 align:start position:10% line:84.66% size:80% For you musicians, it's the note 19:56.833 --> 19:58.166 align:start position:10% line:84.66% size:5% A. 19:58.166 --> 19:59.400 align:start position:10% line:84.66% size:80% Speaking of music, back on Earth 19:59.400 --> 20:00.800 align:start position:10% line:84.66% size:52.5% we have things called 20:00.800 --> 20:01.866 align:start position:10% line:84.66% size:27.5% orchestras. 20:01.866 --> 20:04.300 align:start position:10% line:84.66% size:55% Do you have them here? 20:04.300 --> 20:05.566 align:start position:10% line:84.66% size:67.5% Well, a bunch of people sit 20:05.566 --> 20:07.433 align:start position:10% line:84.66% size:77.5% around with musical instruments 20:07.433 --> 20:09.366 align:start position:10% line:84.66% size:70% and they play the same music 20:09.366 --> 20:11.100 align:start position:10% line:84.66% size:67.5% with different instruments. 20:11.100 --> 20:12.466 align:start position:10% line:84.66% size:77.5% One of the instruments that our 20:12.466 --> 20:14.066 align:start position:10% line:84.66% size:72.5% Earth children often learn to 20:14.066 --> 20:15.700 align:start position:10% line:84.66% size:47.5% play is a recorder. 20:15.700 --> 20:17.566 align:start position:10% line:84.66% size:77.5% I never learned to play it when 20:17.566 --> 20:18.900 align:start position:10% line:84.66% size:80% I was young back on Earth, but I 20:18.900 --> 20:20.200 align:start position:10% line:84.66% size:80% can play a few notes and let you 20:20.200 --> 20:21.466 align:start position:10% line:84.66% size:72.5% see what it looks like on the 20:21.466 --> 20:23.500 align:start position:10% line:84.66% size:32.5% oscilloscope. 20:23.500 --> 20:26.100 align:start position:10% line:84.66% size:42.5% [series of notes] 20:30.433 --> 20:33.433 align:start position:10% line:84.66% size:25% [applause] 20:35.833 --> 20:37.033 align:start position:10% line:84.66% size:67.5% That's how you can tell one 20:37.033 --> 20:38.433 align:start position:10% line:84.66% size:77.5% musical instrument from another 20:38.433 --> 20:39.600 align:start position:10% line:84.66% size:72.5% even when they're playing the 20:39.600 --> 20:40.766 align:start position:10% line:84.66% size:25% same note. 20:40.766 --> 20:41.966 align:start position:10% line:84.66% size:55% Every instrument has a 20:41.966 --> 20:43.566 align:start position:10% line:84.66% size:55% distinctive wave shape 20:43.566 --> 20:45.133 align:start position:10% line:84.66% size:77.5% associated with that particular 20:45.133 --> 20:46.500 align:start position:10% line:84.66% size:17.5% device. 20:46.500 --> 20:48.400 align:start position:10% line:84.66% size:72.5% Back on Earth we have lots of 20:48.400 --> 20:50.066 align:start position:10% line:84.66% size:62.5% sports, and sometimes the 20:50.066 --> 20:51.800 align:start position:10% line:84.66% size:55% referee has a whistle. 20:51.800 --> 20:53.166 align:start position:10% line:84.66% size:75% When they want to play to stop 20:53.166 --> 20:54.400 align:start position:10% line:84.66% size:55% they blow the whistle. 20:54.400 --> 20:55.533 align:start position:10% line:84.66% size:62.5% Let's look at this on the 20:55.533 --> 20:56.666 align:start position:10% line:84.66% size:32.5% oscilloscope. 20:56.666 --> 21:00.333 align:start position:10% line:84.66% size:40% [whistle tweets] 21:00.333 --> 21:02.033 align:start position:10% line:84.66% size:67.5% That's a rather complicated 21:02.033 --> 21:03.233 align:start position:10% line:84.66% size:15% sound. 21:03.233 --> 21:04.333 align:start position:10% line:84.66% size:72.5% Did you know there are sounds 21:04.333 --> 21:05.800 align:start position:10% line:84.66% size:37.5% you can't hear? 21:05.800 --> 21:07.000 align:start position:10% line:84.66% size:20% >> Yeah. 21:07.000 --> 21:08.033 align:start position:10% line:84.66% size:52.5% >> What's an example? 21:08.033 --> 21:09.200 align:start position:10% line:84.66% size:70% A dog whistle, that's right. 21:09.200 --> 21:10.533 align:start position:10% line:84.66% size:62.5% Do you have dogs on Mars? 21:10.533 --> 21:11.900 align:start position:10% line:84.66% size:20% >> Yeah. 21:11.900 --> 21:13.166 align:start position:10% line:84.66% size:77.5% >> We have lots of dogs back on 21:13.166 --> 21:14.733 align:start position:10% line:84.66% size:72.5% Earth, and sometimes we train 21:14.733 --> 21:16.366 align:start position:10% line:84.66% size:75% the dog to come when they hear 21:16.366 --> 21:17.933 align:start position:10% line:84.66% size:32.5% this whistle. 21:17.933 --> 21:19.566 align:start position:10% line:84.66% size:80% The whistle is such a high pitch 21:19.566 --> 21:21.500 align:start position:10% line:84.66% size:77.5% that most humans can't hear it. 21:21.500 --> 21:22.700 align:start position:10% line:84.66% size:72.5% But the dogs can hear it, and 21:22.700 --> 21:23.866 align:start position:10% line:84.66% size:72.5% you can train the dog to come 21:23.866 --> 21:25.233 align:start position:10% line:84.66% size:67.5% when they hear the whistle. 21:25.233 --> 21:26.400 align:start position:10% line:84.66% size:52.5% I'm going to blow it. 21:26.400 --> 21:27.466 align:start position:10% line:84.66% size:80% Some of you Martians may be able 21:27.466 --> 21:28.766 align:start position:10% line:84.66% size:27.5% to hear it. 21:28.766 --> 21:30.033 align:start position:10% line:84.66% size:80% But even if you can't, you'll be 21:30.033 --> 21:31.366 align:start position:10% line:84.66% size:77.5% able to see on the oscilloscope 21:31.366 --> 21:32.733 align:start position:10% line:84.66% size:62.5% that it's making a sound. 21:32.733 --> 21:33.900 align:start position:10% line:84.66% size:27.5% Here we go. 21:33.900 --> 21:36.466 align:start position:10% line:84.66% size:27.5% [dog barks] 21:38.833 --> 21:41.566 align:start position:10% line:84.66% size:60% That's where Rover went! 21:41.566 --> 21:45.900 align:start position:10% line:84.66% size:55% ♪ Fly me to the moon ♪ 21:45.900 --> 21:47.800 align:start position:10% line:84.66% size:37.5% ♪ Let me play ♪ 21:47.800 --> 21:49.366 align:start position:10% line:84.66% size:12.5% Wait! 21:49.366 --> 21:50.500 align:start position:10% line:84.66% size:32.5% I hear music. 21:50.500 --> 21:51.700 align:start position:10% line:84.66% size:45% But that can't be. 21:51.700 --> 21:52.866 align:start position:10% line:84.66% size:35% We're on Mars. 21:52.866 --> 21:53.966 align:start position:10% line:84.66% size:72.5% There's no atmosphere here on 21:53.966 --> 21:55.033 align:start position:10% line:84.66% size:70% Mars for the sound to travel 21:55.033 --> 21:56.133 align:start position:10% line:84.66% size:77.5% through, so I must be imagining 21:56.133 --> 21:58.066 align:start position:10% line:84.66% size:17.5% things. 21:58.066 --> 21:59.200 align:start position:10% line:84.66% size:25% >> Oh, oh! 21:59.200 --> 22:01.566 align:start position:10% line:84.66% size:32.5% My apologies! 22:01.566 --> 22:02.933 align:start position:10% line:84.66% size:37.5% My name's Mike. 22:02.933 --> 22:04.066 align:start position:10% line:84.66% size:75% I'm the Minister of Sound here 22:04.066 --> 22:05.200 align:start position:10% line:84.66% size:20% on Mars. 22:05.200 --> 22:06.333 align:start position:10% line:84.66% size:80% I'm so excited to meet the Great 22:06.333 --> 22:07.666 align:start position:10% line:84.66% size:67.5% Sprott, I forgot to move my 22:07.666 --> 22:09.600 align:start position:10% line:84.66% size:12.5% lips! 22:09.600 --> 22:10.800 align:start position:10% line:84.66% size:62.5% You see, sound works very 22:10.800 --> 22:12.133 align:start position:10% line:84.66% size:77.5% differently here on Mars, so we 22:12.133 --> 22:13.300 align:start position:10% line:84.66% size:70% Martians have learned how to 22:13.300 --> 22:14.366 align:start position:10% line:84.66% size:72.5% communicate directly with our 22:14.366 --> 22:15.433 align:start position:10% line:84.66% size:17.5% brains. 22:15.433 --> 22:16.966 align:start position:10% line:84.66% size:77.5% But we also learned to move our 22:16.966 --> 22:18.433 align:start position:10% line:84.66% size:80% lips to make Earthlings a little 22:18.433 --> 22:19.633 align:start position:10% line:84.66% size:42.5% more comfortable. 22:19.633 --> 22:20.800 align:start position:10% line:84.66% size:52.5% >> Sound is one of my 22:20.800 --> 22:22.000 align:start position:10% line:84.66% size:65% favorite areas of physics. 22:22.000 --> 22:23.466 align:start position:10% line:84.66% size:77.5% I want to hear more about this. 22:23.466 --> 22:25.100 align:start position:10% line:84.66% size:35% >> Absolutely. 22:25.100 --> 22:26.300 align:start position:10% line:84.66% size:62.5% Sound is a vibration some 22:26.300 --> 22:27.800 align:start position:10% line:84.66% size:22.5% material. 22:27.800 --> 22:29.966 align:start position:10% line:84.66% size:75% And to demonstrate that I have 22:29.966 --> 22:31.100 align:start position:10% line:84.66% size:62.5% this coiled piece of wire 22:31.100 --> 22:32.166 align:start position:10% line:84.66% size:25% back here. 22:32.166 --> 22:36.366 align:start position:10% line:84.66% size:80% On Earth call this a "slin-kee". 22:36.366 --> 22:38.000 align:start position:10% line:84.66% size:80% In a sound wave, the material is 22:38.000 --> 22:40.633 align:start position:10% line:84.66% size:65% stretched apart and pushed 22:40.633 --> 22:42.100 align:start position:10% line:84.66% size:22.5% together. 22:42.100 --> 22:43.333 align:start position:10% line:84.66% size:75% You get a wave that looks like 22:43.333 --> 22:44.433 align:start position:10% line:84.66% size:12.5% this. 22:44.433 --> 22:45.533 align:start position:10% line:84.66% size:72.5% This is called a longitudinal 22:45.533 --> 22:46.666 align:start position:10% line:84.66% size:12.5% wave. 22:46.666 --> 22:48.533 align:start position:10% line:84.66% size:25% [applause] 22:49.800 --> 22:52.366 align:start position:10% line:84.66% size:65% Sound depends on pressure, 22:52.366 --> 22:54.166 align:start position:10% line:84.66% size:67.5% temperature and the kind of 22:54.166 --> 22:55.666 align:start position:10% line:84.66% size:65% material that it is moving 22:55.666 --> 22:56.933 align:start position:10% line:84.66% size:20% through. 22:56.933 --> 22:59.133 align:start position:10% line:84.66% size:70% Earth's atmosphere is mostly 22:59.133 --> 23:00.966 align:start position:10% line:84.66% size:50% Nitrogen and Oxygen. 23:00.966 --> 23:02.400 align:start position:10% line:84.66% size:70% Earthlings call this mixture 23:02.400 --> 23:04.733 align:start position:10% line:84.66% size:15% "air". 23:04.733 --> 23:06.833 align:start position:10% line:84.66% size:70% The speed of sound in air is 23:06.833 --> 23:09.066 align:start position:10% line:84.66% size:72.5% about 340 meters per seconds. 23:09.066 --> 23:12.633 align:start position:10% line:84.66% size:77.5% That's over 760 miles per hour! 23:12.633 --> 23:15.433 align:start position:10% line:84.66% size:67.5% Frequency is how fast those 23:15.433 --> 23:16.900 align:start position:10% line:84.66% size:62.5% sound waves travel past a 23:16.900 --> 23:18.433 align:start position:10% line:84.66% size:35% certain point. 23:18.433 --> 23:20.133 align:start position:10% line:84.66% size:80% To demonstrate that I've created 23:20.133 --> 23:21.300 align:start position:10% line:84.66% size:30% this device. 23:21.300 --> 23:23.666 align:start position:10% line:84.66% size:60% I call this a "Barsoom". 23:23.666 --> 23:25.466 align:start position:10% line:84.66% size:75% I need a Martian child to help 23:25.466 --> 23:27.433 align:start position:10% line:84.66% size:32.5% me with this. 23:27.433 --> 23:28.533 align:start position:10% line:84.66% size:70% Who could I have help me out 23:28.533 --> 23:30.200 align:start position:10% line:84.66% size:12.5% here? 23:30.200 --> 23:31.666 align:start position:10% line:84.66% size:35% How about you. 23:31.666 --> 23:34.566 align:start position:10% line:84.66% size:67.5% This young lady right here. 23:34.566 --> 23:40.233 align:start position:10% line:84.66% size:32.5% Come on down. 23:40.233 --> 23:41.400 align:start position:10% line:84.66% size:45% What is your name? 23:41.400 --> 23:42.500 align:start position:10% line:84.66% size:22.5% >> Molly. 23:42.500 --> 23:43.633 align:start position:10% line:84.66% size:77.5% >> Molly, that's a good Martian 23:43.633 --> 23:44.800 align:start position:10% line:84.66% size:12.5% name. 23:44.800 --> 23:46.100 align:start position:10% line:84.66% size:80% Now Molly, the way this works is 23:46.100 --> 23:47.566 align:start position:10% line:84.66% size:80% the sound that comes out depends 23:47.566 --> 23:49.033 align:start position:10% line:84.66% size:67.5% on the length of this tube, 23:49.033 --> 23:50.266 align:start position:10% line:84.66% size:75% and it also depends on the gas 23:50.266 --> 23:51.533 align:start position:10% line:84.66% size:35% that's inside. 23:51.533 --> 23:53.133 align:start position:10% line:84.66% size:72.5% We're going to start off with 23:53.133 --> 23:54.466 align:start position:10% line:84.66% size:52.5% some Earth air, okay? 23:54.466 --> 23:55.700 align:start position:10% line:84.66% size:72.5% What I want you to do is push 23:55.700 --> 23:56.933 align:start position:10% line:84.66% size:70% those two things together as 23:56.933 --> 23:58.133 align:start position:10% line:84.66% size:40% hard as you can. 23:58.133 --> 24:01.500 align:start position:10% line:84.66% size:47.5% [low pitched sound] 24:01.500 --> 24:03.000 align:start position:10% line:84.66% size:72.5% Very good, okay, that's good. 24:03.000 --> 24:05.833 align:start position:10% line:84.66% size:77.5% So that's what air sounds like. 24:05.833 --> 24:09.166 align:start position:10% line:84.66% size:72.5% This balloon contains helium. 24:09.166 --> 24:11.233 align:start position:10% line:84.66% size:77.5% Now helium is a very light gas. 24:11.233 --> 24:12.666 align:start position:10% line:84.66% size:77.5% The speed of sound in helium is 24:12.666 --> 24:14.533 align:start position:10% line:84.66% size:65% almost three times faster! 24:14.533 --> 24:15.966 align:start position:10% line:84.66% size:77.5% The sound waves bounce back and 24:15.966 --> 24:17.500 align:start position:10% line:84.66% size:60% forth faster, and make a 24:17.500 --> 24:18.600 align:start position:10% line:84.66% size:72.5% higher frequency, or a higher 24:18.600 --> 24:19.800 align:start position:10% line:84.66% size:15% pitch! 24:19.800 --> 24:20.900 align:start position:10% line:84.66% size:57.5% Let's try this one out. 24:20.900 --> 24:22.866 align:start position:10% line:84.66% size:55% [higher pitched sound] 24:22.866 --> 24:25.433 align:start position:10% line:84.66% size:42.5% That's very good. 24:25.433 --> 24:27.466 align:start position:10% line:84.66% size:70% This balloon contains sulfur 24:27.466 --> 24:28.633 align:start position:10% line:84.66% size:30% hexafluorid. 24:28.633 --> 24:30.433 align:start position:10% line:84.66% size:55% It's a very dense gas. 24:30.433 --> 24:31.766 align:start position:10% line:84.66% size:72.5% The speed of sound in this is 24:31.766 --> 24:33.200 align:start position:10% line:84.66% size:70% only about one-third as fast 24:33.200 --> 24:34.333 align:start position:10% line:84.66% size:30% that in air! 24:34.333 --> 24:35.333 align:start position:10% line:84.66% size:67.5% Let's see what happens with 24:35.333 --> 24:36.566 align:start position:10% line:84.66% size:12.5% this. 24:36.566 --> 24:39.933 align:start position:10% line:84.66% size:62.5% [sounds goes high to low] 24:39.933 --> 24:41.833 align:start position:10% line:84.66% size:80% The sound waves bounce back much 24:41.833 --> 24:43.500 align:start position:10% line:84.66% size:67.5% more slowly, so got a lower 24:43.500 --> 24:45.500 align:start position:10% line:84.66% size:70% frequency, or a lower pitch. 24:45.500 --> 24:47.000 align:start position:10% line:84.66% size:75% This last one contains Martian 24:47.000 --> 24:48.133 align:start position:10% line:84.66% size:27.5% atmosphere. 24:48.133 --> 24:49.733 align:start position:10% line:84.66% size:62.5% Mars atmosphere is almost 24:49.733 --> 24:51.466 align:start position:10% line:84.66% size:65% completely carbon dioxide. 24:51.466 --> 24:52.733 align:start position:10% line:84.66% size:80% Listen carefully and here how it 24:52.733 --> 24:54.700 align:start position:10% line:84.66% size:70% compares to the other gases. 24:54.700 --> 24:57.766 align:start position:10% line:84.66% size:40% [very low sound] 24:57.766 --> 24:59.333 align:start position:10% line:84.66% size:57.5% Now, what do you think? 24:59.333 --> 25:00.533 align:start position:10% line:84.66% size:80% Do you think that's pretty close 25:00.533 --> 25:01.633 align:start position:10% line:84.66% size:17.5% to air? 25:01.633 --> 25:02.666 align:start position:10% line:84.66% size:80% Do you think it's a little lower 25:02.666 --> 25:03.866 align:start position:10% line:84.66% size:25% or higher? 25:03.866 --> 25:05.133 align:start position:10% line:84.66% size:45% >> A little lower. 25:05.133 --> 25:06.200 align:start position:10% line:84.66% size:80% >> Yeah, it's a little bit lower 25:06.200 --> 25:07.200 align:start position:10% line:84.66% size:22.5% than air. 25:07.200 --> 25:08.300 align:start position:10% line:84.66% size:77.5% Very good, you have a very good 25:08.300 --> 25:09.400 align:start position:10% line:84.66% size:10% ear. 25:09.400 --> 25:10.466 align:start position:10% line:84.66% size:67.5% That's about right, because 25:10.466 --> 25:11.666 align:start position:10% line:84.66% size:65% carbon dioxide is a little 25:11.666 --> 25:12.800 align:start position:10% line:84.66% size:40% denser than air. 25:12.800 --> 25:13.966 align:start position:10% line:84.66% size:70% The speed of sound in carbon 25:13.966 --> 25:15.100 align:start position:10% line:84.66% size:75% dioxide is a little lower than 25:15.100 --> 25:16.233 align:start position:10% line:84.66% size:77.5% that of air, so we have a lower 25:16.233 --> 25:17.300 align:start position:10% line:84.66% size:15% pitch. 25:17.300 --> 25:18.366 align:start position:10% line:84.66% size:67.5% Molly, you did a great job. 25:18.366 --> 25:19.466 align:start position:10% line:84.66% size:50% Thank you very much. 25:19.466 --> 25:20.533 align:start position:10% line:84.66% size:72.5% Let's give her a big round of 25:20.533 --> 25:21.800 align:start position:10% line:84.66% size:22.5% applause. 25:21.800 --> 25:23.500 align:start position:10% line:84.66% size:25% [applause] 25:23.500 --> 25:25.466 align:start position:10% line:84.66% size:72.5% As I mentioned earlier, sound 25:25.466 --> 25:27.200 align:start position:10% line:84.66% size:75% works very differently on Mars 25:27.200 --> 25:28.933 align:start position:10% line:84.66% size:55% than it does on Earth. 25:28.933 --> 25:30.900 align:start position:10% line:84.66% size:77.5% This has to do with the density 25:30.900 --> 25:32.666 align:start position:10% line:84.66% size:65% of the Martian atmosphere. 25:32.666 --> 25:33.766 align:start position:10% line:84.66% size:77.5% Mars's atmosphere is very, very 25:33.766 --> 25:35.566 align:start position:10% line:84.66% size:12.5% thin. 25:37.600 --> 25:39.800 align:start position:10% line:84.66% size:67.5% So what we're doing here is 25:39.800 --> 25:41.566 align:start position:10% line:84.66% size:70% we're pumping the air out of 25:41.566 --> 25:42.833 align:start position:10% line:84.66% size:80% this large jar here, to simulate 25:42.833 --> 25:44.166 align:start position:10% line:84.66% size:75% Mars's atmosphere, how thin it 25:44.166 --> 25:45.400 align:start position:10% line:84.66% size:7.5% is. 25:45.400 --> 25:46.566 align:start position:10% line:84.66% size:67.5% We also have a sound making 25:46.566 --> 25:47.900 align:start position:10% line:84.66% size:77.5% device in there, a speaker, and 25:47.900 --> 25:49.200 align:start position:10% line:84.66% size:32.5% a microphone. 25:49.200 --> 25:50.466 align:start position:10% line:84.66% size:80% Oh, I should also mention that I 25:50.466 --> 25:51.833 align:start position:10% line:84.66% size:72.5% brought my pets along to help 25:51.833 --> 25:53.466 align:start position:10% line:84.66% size:45% demonstrate today. 25:53.466 --> 25:56.033 align:start position:10% line:84.66% size:65% This is Phobos and Deimos, 25:56.033 --> 25:57.933 align:start position:10% line:84.66% size:70% named after the Mars' moons. 25:57.933 --> 25:59.100 align:start position:10% line:84.66% size:75% I've been teaching them how to 25:59.100 --> 26:01.133 align:start position:10% line:84.66% size:52.5% dance to Earth music. 26:01.133 --> 26:02.166 align:start position:10% line:84.66% size:77.5% Phobos is getting quite good at 26:02.166 --> 26:04.400 align:start position:10% line:84.66% size:7.5% it. 26:04.400 --> 26:06.266 align:start position:10% line:84.66% size:77.5% Deimos just kind of sits there. 26:06.266 --> 26:07.600 align:start position:10% line:84.66% size:25% [laughter] 26:07.600 --> 26:09.766 align:start position:10% line:84.66% size:72.5% Oh, well, can't win them all. 26:09.766 --> 26:11.066 align:start position:10% line:84.66% size:75% What we're going to do here is 26:11.066 --> 26:12.266 align:start position:10% line:84.66% size:70% we're going to play a little 26:12.266 --> 26:13.433 align:start position:10% line:84.66% size:57.5% Earth music through the 26:13.433 --> 26:16.133 align:start position:10% line:84.66% size:60% loudspeaker in this jar. 26:16.133 --> 26:17.300 align:start position:10% line:84.66% size:67.5% We're going to hear what it 26:17.300 --> 26:18.600 align:start position:10% line:84.66% size:72.5% sounds like through the thin, 26:18.600 --> 26:20.000 align:start position:10% line:84.66% size:62.5% thin, Martian atmosphere. 26:20.000 --> 26:21.966 align:start position:10% line:84.66% size:70% Okay, hang on just a moment. 26:21.966 --> 26:24.666 align:start position:10% line:84.66% size:50% [bell rings faintly] 26:24.666 --> 26:29.600 align:start position:10% line:84.66% size:77.5% Let's hear what it sounds like. 26:29.600 --> 26:34.800 align:start position:10% line:84.66% size:50% [music plays softly] 26:34.800 --> 26:36.600 align:start position:10% line:84.66% size:40% Can you hear it? 26:36.600 --> 26:37.733 align:start position:10% line:84.66% size:72.5% You can't hear it very easily 26:37.733 --> 26:39.000 align:start position:10% line:84.66% size:75% though, it's very, very faint. 26:39.000 --> 26:40.166 align:start position:10% line:84.66% size:62.5% The sound does not travel 26:40.166 --> 26:41.300 align:start position:10% line:84.66% size:70% through that thin atmosphere 26:41.300 --> 26:42.866 align:start position:10% line:84.66% size:25% very well. 26:42.866 --> 26:44.066 align:start position:10% line:84.66% size:77.5% What we're going to do is we're 26:44.066 --> 26:45.266 align:start position:10% line:84.66% size:70% going to let this Earth-type 26:45.266 --> 26:46.333 align:start position:10% line:84.66% size:67.5% atmosphere back in the jar. 26:46.333 --> 26:47.366 align:start position:10% line:84.66% size:75% Let's see what difference that 26:47.366 --> 26:49.566 align:start position:10% line:84.66% size:15% makes. 26:49.566 --> 26:50.800 align:start position:10% line:84.66% size:72.5% Let me put this on hold for a 26:50.800 --> 26:53.733 align:start position:10% line:84.66% size:17.5% second. 26:53.733 --> 26:57.766 align:start position:10% line:84.66% size:32.5% [air hissing] 26:57.766 --> 26:59.100 align:start position:10% line:84.66% size:75% Now we're letting the air back 26:59.100 --> 27:00.433 align:start position:10% line:84.66% size:42.5% in the jar there. 27:00.433 --> 27:01.500 align:start position:10% line:84.66% size:65% Can you help me out there? 27:01.500 --> 27:03.066 align:start position:10% line:84.66% size:75% Can you see the numbers there? 27:03.066 --> 27:04.133 align:start position:10% line:84.66% size:27.5% [inaudible] 27:04.133 --> 27:05.300 align:start position:10% line:84.66% size:72.5% Let me know when that gets to 27:05.300 --> 27:06.566 align:start position:10% line:84.66% size:12.5% zero. 27:06.566 --> 27:07.800 align:start position:10% line:84.66% size:27.5% [inaudible] 27:07.800 --> 27:09.966 align:start position:10% line:84.66% size:35% Getting close? 27:09.966 --> 27:14.266 align:start position:10% line:84.66% size:30% Three, two-- 27:14.266 --> 27:16.366 align:start position:10% line:84.66% size:67.5% I think we're almost there. 27:16.366 --> 27:18.100 align:start position:10% line:84.66% size:72.5% All right, let's see what the 27:18.100 --> 27:19.233 align:start position:10% line:84.66% size:45% difference is now. 27:19.233 --> 27:21.833 align:start position:10% line:84.66% size:50% [music plays loudly] 27:29.300 --> 27:31.200 align:start position:10% line:84.66% size:30% There we go. 27:31.200 --> 27:35.200 align:start position:10% line:84.66% size:20% Come on. 27:35.200 --> 27:36.366 align:start position:10% line:84.66% size:80% Do you notice how much louder it 27:36.366 --> 27:38.600 align:start position:10% line:84.66% size:17.5% is now? 27:38.600 --> 27:39.933 align:start position:10% line:84.66% size:67.5% Sound likes to move through 27:39.933 --> 27:42.766 align:start position:10% line:84.66% size:80% materials the denser the better. 27:42.766 --> 27:44.066 align:start position:10% line:84.66% size:77.5% The denser it is, the louder it 27:44.066 --> 27:46.000 align:start position:10% line:84.66% size:20% will be. 27:46.000 --> 27:48.066 align:start position:10% line:84.66% size:70% So now you understand why we 27:48.066 --> 27:49.866 align:start position:10% line:84.66% size:77.5% Martians learned to communicate 27:49.866 --> 27:51.066 align:start position:10% line:84.66% size:62.5% directly with our brains. 27:51.066 --> 27:52.200 align:start position:10% line:84.66% size:67.5% If we tried to talk to each 27:52.200 --> 27:53.400 align:start position:10% line:84.66% size:80% other, even if I was shouting at 27:53.400 --> 27:54.666 align:start position:10% line:84.66% size:80% the top of my lungs and you were 27:54.666 --> 27:56.466 align:start position:10% line:84.66% size:80% standing right there, I could be 27:56.466 --> 27:57.700 align:start position:10% line:84.66% size:72.5% shouting and you would barely 27:57.700 --> 27:59.400 align:start position:10% line:84.66% size:75% hear me through that very thin 27:59.400 --> 28:03.800 align:start position:10% line:84.66% size:47.5% Martian atmosphere. 28:03.800 --> 28:05.400 align:start position:10% line:84.66% size:47.5% What are you doing? 28:05.400 --> 28:06.533 align:start position:10% line:84.66% size:40% [computer voice] 28:06.533 --> 28:07.866 align:start position:10% line:84.66% size:75% >> I'm using my apple computer 28:07.866 --> 28:09.233 align:start position:10% line:84.66% size:70% to translate from Martian to 28:09.233 --> 28:10.700 align:start position:10% line:84.66% size:20% English. 28:10.700 --> 28:11.800 align:start position:10% line:84.66% size:80% >> That's not an Apple computer. 28:11.800 --> 28:15.833 align:start position:10% line:84.66% size:25% [laughter] 28:15.833 --> 28:17.200 align:start position:10% line:84.66% size:35% >> Yes, it is! 28:17.200 --> 28:18.466 align:start position:10% line:84.66% size:62.5% Steve Jobs was working on 28:18.466 --> 28:20.633 align:start position:10% line:84.66% size:75% it just before he died, and he 28:20.633 --> 28:23.066 align:start position:10% line:84.66% size:67.5% sent me the plans by email. 28:23.066 --> 28:25.266 align:start position:10% line:84.66% size:80% >> That's a fantastic invention! 28:25.266 --> 28:27.033 align:start position:10% line:84.66% size:60% That will really help us 28:27.033 --> 28:28.133 align:start position:10% line:84.66% size:57.5% communicate better with 28:28.133 --> 28:29.333 align:start position:10% line:84.66% size:27.5% Earthlings. 28:29.333 --> 28:31.766 align:start position:10% line:84.66% size:67.5% Thank you for sharing that. 28:33.433 --> 28:35.366 align:start position:10% line:84.66% size:25% [applause] 28:39.866 --> 28:41.000 align:start position:10% line:84.66% size:65% >> Let me try some of that 28:41.000 --> 28:42.266 align:start position:10% line:84.66% size:67.5% telepathic singing you were 28:42.266 --> 28:43.366 align:start position:10% line:84.66% size:32.5% doing before. 28:43.366 --> 28:47.066 align:start position:10% line:84.66% size:35% >> Oh, please. 28:47.066 --> 28:49.066 align:start position:10% line:84.66% size:35% [music starts] 28:53.300 --> 28:55.533 align:start position:10% line:84.66% size:62.5% Oh no, not MARS by Holst. 28:55.533 --> 28:57.266 align:start position:10% line:84.66% size:80% That tune is so played out here! 28:57.266 --> 28:58.300 align:start position:10% line:84.66% size:37.5% I've got to go. 28:58.300 --> 29:01.366 align:start position:10% line:84.66% size:15% Sorry. 29:01.366 --> 29:04.033 align:start position:10% line:84.66% size:25% [applause] 29:07.966 --> 29:09.066 align:start position:10% line:84.66% size:72.5% >> You know that's really not 29:09.066 --> 29:10.400 align:start position:10% line:84.66% size:72.5% an Apple computer that he was 29:10.400 --> 29:11.666 align:start position:10% line:84.66% size:35% talking about. 29:11.666 --> 29:13.233 align:start position:10% line:84.66% size:60% That was our Mars Mapple 29:13.233 --> 29:15.000 align:start position:10% line:84.66% size:22.5% computer. 29:15.000 --> 29:17.100 align:start position:10% line:84.66% size:72.5% And of course we have M-pads, 29:17.100 --> 29:20.700 align:start position:10% line:84.66% size:67.5% M-pods, M-phones and MP-3s. 29:20.700 --> 29:22.500 align:start position:10% line:84.66% size:62.5% This all comes at a great 29:22.500 --> 29:24.366 align:start position:10% line:84.66% size:55% cost to us, because it 29:24.366 --> 29:26.266 align:start position:10% line:84.66% size:80% demands a so much electricity to 29:26.266 --> 29:28.100 align:start position:10% line:84.66% size:60% power all these devices. 29:28.100 --> 29:29.466 align:start position:10% line:84.66% size:72.5% By the way, do you know why a 29:29.466 --> 29:30.800 align:start position:10% line:84.66% size:42.5% transformer hums? 29:30.800 --> 29:31.933 align:start position:10% line:84.66% size:27.5% >> No, why? 29:31.933 --> 29:33.000 align:start position:10% line:84.66% size:75% >> Because it doesn't know the 29:33.000 --> 29:34.466 align:start position:10% line:84.66% size:15% words. 29:34.466 --> 29:35.633 align:start position:10% line:84.66% size:80% But anyhow, maybe you could show 29:35.633 --> 29:36.866 align:start position:10% line:84.66% size:57.5% us one of your favorite 29:36.866 --> 29:38.500 align:start position:10% line:84.66% size:67.5% electricity demonstrations? 29:38.500 --> 29:39.466 align:start position:10% line:84.66% size:45% >> We have lots of 29:39.466 --> 29:40.766 align:start position:10% line:84.66% size:65% electrical gadgets back on 29:40.766 --> 29:41.866 align:start position:10% line:84.66% size:77.5% Earth, as I know you do here on 29:41.866 --> 29:43.466 align:start position:10% line:84.66% size:32.5% Mars as well. 29:43.466 --> 29:44.500 align:start position:10% line:84.66% size:77.5% But we sometimes have something 29:44.500 --> 29:45.500 align:start position:10% line:84.66% size:37.5% you don't have. 29:45.500 --> 29:47.466 align:start position:10% line:84.66% size:17.5% We have 29:47.466 --> 29:48.833 align:start position:10% line:84.66% size:70% electrical discharges in the 29:48.833 --> 29:49.900 align:start position:10% line:84.66% size:60% atmosphere of the Earth. 29:49.900 --> 29:51.466 align:start position:10% line:84.66% size:52.5% We call it lightning. 29:51.466 --> 29:52.633 align:start position:10% line:84.66% size:72.5% I want to demonstrate that to 29:52.633 --> 29:54.900 align:start position:10% line:84.66% size:75% you, if one you Martians would 29:54.900 --> 29:56.966 align:start position:10% line:84.66% size:45% volunteer to help. 29:56.966 --> 29:58.033 align:start position:10% line:84.66% size:50% Okay, how about you. 29:58.033 --> 30:00.266 align:start position:10% line:84.66% size:22.5% Yup, you. 30:00.266 --> 30:02.733 align:start position:10% line:84.66% size:42.5% Run on down here. 30:02.733 --> 30:04.300 align:start position:10% line:84.66% size:72.5% We're going to take you where 30:04.300 --> 30:05.900 align:start position:10% line:84.66% size:47.5% there is lightning. 30:05.900 --> 30:07.000 align:start position:10% line:84.66% size:65% Maybe you don't know about 30:07.000 --> 30:08.066 align:start position:10% line:84.66% size:25% lightning. 30:08.066 --> 30:09.100 align:start position:10% line:84.66% size:60% Turn around and face the 30:09.100 --> 30:10.100 align:start position:10% line:84.66% size:22.5% audience. 30:10.100 --> 30:11.100 align:start position:10% line:84.66% size:42.5% What's your name? 30:11.100 --> 30:12.100 align:start position:10% line:84.66% size:20% >> Eric. 30:12.100 --> 30:13.100 align:start position:10% line:84.66% size:70% >> Eric, okay Eric, have you 30:13.100 --> 30:14.500 align:start position:10% line:84.66% size:50% ever seen lightning? 30:14.500 --> 30:15.633 align:start position:10% line:84.66% size:25% >> Uh-huh. 30:15.633 --> 30:16.700 align:start position:10% line:84.66% size:30% >> You have. 30:16.700 --> 30:18.066 align:start position:10% line:84.66% size:45% Does it scare you? 30:18.066 --> 30:19.166 align:start position:10% line:84.66% size:22.5% >> Kinda. 30:19.166 --> 30:20.300 align:start position:10% line:84.66% size:75% >> Well, it should kinda scare 30:20.300 --> 30:21.533 align:start position:10% line:84.66% size:72.5% you, because lightning can be 30:21.533 --> 30:22.600 align:start position:10% line:84.66% size:25% dangerous. 30:22.600 --> 30:23.600 align:start position:10% line:84.66% size:67.5% We're going to put you in a 30:23.600 --> 30:25.066 align:start position:10% line:84.66% size:70% place that's very, very safe 30:25.066 --> 30:26.233 align:start position:10% line:84.66% size:12.5% Eric. 30:26.233 --> 30:27.500 align:start position:10% line:84.66% size:75% Turn to you left, walk over to 30:27.500 --> 30:29.066 align:start position:10% line:84.66% size:25% this cage. 30:29.066 --> 30:31.066 align:start position:10% line:84.66% size:47.5% [death march music] 30:33.733 --> 30:35.366 align:start position:10% line:84.66% size:80% And have a seat in what on Earth 30:35.366 --> 30:37.133 align:start position:10% line:84.66% size:65% we call an electric chair. 30:37.133 --> 30:39.500 align:start position:10% line:84.66% size:32.5% [scary chord] 30:39.500 --> 30:40.866 align:start position:10% line:84.66% size:62.5% Over to Eric's right is a 30:40.866 --> 30:43.000 align:start position:10% line:84.66% size:77.5% million volt Tesla Coil, and it 30:43.000 --> 30:44.833 align:start position:10% line:84.66% size:62.5% makes bolts of lightning. 30:44.833 --> 30:46.000 align:start position:10% line:84.66% size:77.5% As long as you don't stick your 30:46.000 --> 30:47.133 align:start position:10% line:84.66% size:70% fingers through the cage you 30:47.133 --> 30:49.766 align:start position:10% line:84.66% size:57.5% shouldn't feel a thing. 30:49.766 --> 30:51.833 align:start position:10% line:84.66% size:55% [electricity crackles] 30:56.900 --> 30:58.866 align:start position:10% line:84.66% size:37.5% Thank you Eric. 30:58.866 --> 31:00.466 align:start position:10% line:84.66% size:25% [applause] 31:05.433 --> 31:09.533 align:start position:10% line:84.66% size:37.5% [silly singing] 31:09.533 --> 31:11.800 align:start position:10% line:84.66% size:62.5% >> Oh, greeting Professor 31:11.800 --> 31:12.900 align:start position:10% line:84.66% size:17.5% Sprott! 31:12.900 --> 31:14.166 align:start position:10% line:84.66% size:60% I am Martin the Martian, 31:14.166 --> 31:15.300 align:start position:10% line:84.66% size:55% Secretary of Energy of 31:15.300 --> 31:16.466 align:start position:10% line:84.66% size:27.5% Sprottania! 31:16.466 --> 31:17.966 align:start position:10% line:84.66% size:77.5% It is my job to ensure that all 31:17.966 --> 31:19.100 align:start position:10% line:84.66% size:60% the Martians have enough 31:19.100 --> 31:20.400 align:start position:10% line:84.66% size:62.5% electricity to watch your 31:20.400 --> 31:22.266 align:start position:10% line:84.66% size:75% broadcasts on Wisconsin Public 31:22.266 --> 31:23.966 align:start position:10% line:84.66% size:27.5% Television. 31:23.966 --> 31:25.100 align:start position:10% line:84.66% size:67.5% May I say that we find your 31:25.100 --> 31:27.733 align:start position:10% line:84.66% size:70% demonstrations electrifying! 31:27.733 --> 31:29.233 align:start position:10% line:84.66% size:17.5% Hahaha. 31:29.233 --> 31:30.466 align:start position:10% line:84.66% size:25% [laughter] 31:30.466 --> 31:32.233 align:start position:10% line:84.66% size:80% We were particularly inspired by 31:32.233 --> 31:33.400 align:start position:10% line:84.66% size:75% the demonstration of the Tesla 31:33.400 --> 31:34.566 align:start position:10% line:84.66% size:12.5% coil. 31:34.566 --> 31:35.933 align:start position:10% line:84.66% size:72.5% When we saw the sparks flying 31:35.933 --> 31:37.133 align:start position:10% line:84.66% size:67.5% through the air we thought, 31:37.133 --> 31:38.466 align:start position:10% line:84.66% size:57.5% perhaps we can transmit 31:38.466 --> 31:39.533 align:start position:10% line:84.66% size:52.5% electricity that way! 31:39.533 --> 31:40.533 align:start position:10% line:84.66% size:60% Do you think that that's 31:40.533 --> 31:41.566 align:start position:10% line:84.66% size:22.5% possible? 31:41.566 --> 31:42.600 align:start position:10% line:84.66% size:70% >> You know, that was Nikola 31:42.600 --> 31:43.766 align:start position:10% line:84.66% size:47.5% Tesla's early idea. 31:43.766 --> 31:44.900 align:start position:10% line:84.66% size:55% He was going to make a 31:44.900 --> 31:46.433 align:start position:10% line:84.66% size:80% gigantic version of one of these 31:46.433 --> 31:48.000 align:start position:10% line:84.66% size:72.5% coils and send electric power 31:48.000 --> 31:49.366 align:start position:10% line:84.66% size:80% all over the Earth without using 31:49.366 --> 31:50.566 align:start position:10% line:84.66% size:15% wires. 31:50.566 --> 31:53.200 align:start position:10% line:84.66% size:77.5% >> Perhaps we can try that now. 31:53.200 --> 31:54.433 align:start position:10% line:84.66% size:20% >> Sure. 31:54.433 --> 31:55.466 align:start position:10% line:84.66% size:75% >> If you would be kind enough 31:55.466 --> 31:56.700 align:start position:10% line:84.66% size:75% to run the Tesla coil again, I 31:56.700 --> 31:57.866 align:start position:10% line:84.66% size:67.5% will hand these fluorescent 31:57.866 --> 31:59.100 align:start position:10% line:84.66% size:70% light bulbs to some of these 31:59.100 --> 32:00.266 align:start position:10% line:84.66% size:62.5% Martians in the audience. 32:00.266 --> 32:01.300 align:start position:10% line:84.66% size:70% Here, would you like to hold 32:01.300 --> 32:02.400 align:start position:10% line:84.66% size:10% one? 32:02.400 --> 32:03.600 align:start position:10% line:84.66% size:35% Take just one. 32:03.600 --> 32:04.600 align:start position:10% line:84.66% size:47.5% Careful, two hands. 32:04.600 --> 32:05.700 align:start position:10% line:84.66% size:30% It is heavy. 32:05.700 --> 32:06.766 align:start position:10% line:84.66% size:57.5% Just one, there you go. 32:06.766 --> 32:07.766 align:start position:10% line:84.66% size:47.5% Would you like one? 32:07.766 --> 32:08.833 align:start position:10% line:84.66% size:25% Two hands. 32:08.833 --> 32:09.866 align:start position:10% line:84.66% size:25% Thank you. 32:09.866 --> 32:11.066 align:start position:10% line:84.66% size:75% And you have one too, and I'll 32:11.066 --> 32:12.233 align:start position:10% line:84.66% size:22.5% hold one. 32:12.233 --> 32:13.666 align:start position:10% line:84.66% size:75% All right, strike up the Tesla 32:13.666 --> 32:16.100 align:start position:10% line:84.66% size:12.5% coil! 32:16.100 --> 32:18.333 align:start position:10% line:84.66% size:55% [electricity crackles] 32:25.166 --> 32:27.000 align:start position:10% line:84.66% size:50% Thank you very much. 32:27.000 --> 32:30.300 align:start position:10% line:84.66% size:25% [applause] 32:30.300 --> 32:31.833 align:start position:10% line:84.66% size:80% Wow, it does take quite a bit of 32:31.833 --> 32:33.333 align:start position:10% line:84.66% size:70% electricity to run the Tesla 32:33.333 --> 32:35.333 align:start position:10% line:84.66% size:75% coil, but Professor Sprott has 32:35.333 --> 32:36.633 align:start position:10% line:84.66% size:75% shown us many ways to generate 32:36.633 --> 32:38.033 align:start position:10% line:84.66% size:30% electricity. 32:38.033 --> 32:40.166 align:start position:10% line:84.66% size:80% For example, static electricity, 32:40.166 --> 32:41.433 align:start position:10% line:84.66% size:75% like when you rub your feet on 32:41.433 --> 32:42.400 align:start position:10% line:84.66% size:70% the carpet in the winter and 32:42.400 --> 32:43.600 align:start position:10% line:84.66% size:42.5% then get a shock. 32:43.600 --> 32:46.266 align:start position:10% line:84.66% size:65% We have a device over here 32:46.266 --> 32:47.433 align:start position:10% line:84.66% size:55% called a Van de Graaff 32:47.433 --> 32:48.633 align:start position:10% line:84.66% size:62.5% Generator, which works on 32:48.633 --> 32:50.466 align:start position:10% line:84.66% size:45% similar principle. 32:50.466 --> 32:52.366 align:start position:10% line:84.66% size:75% In the base there's a strip of 32:52.366 --> 32:54.066 align:start position:10% line:84.66% size:75% cloth that will run around and 32:54.066 --> 32:56.000 align:start position:10% line:84.66% size:80% around when I turn on the motor. 32:56.000 --> 32:57.300 align:start position:10% line:84.66% size:75% It will rub off electrons onto 32:57.300 --> 32:58.966 align:start position:10% line:84.66% size:45% this metal sphere. 32:58.966 --> 33:01.133 align:start position:10% line:84.66% size:70% On top of the metal sphere I 33:01.133 --> 33:02.600 align:start position:10% line:84.66% size:47.5% have an old friend. 33:02.600 --> 33:03.800 align:start position:10% line:84.66% size:72.5% Professor Sprott, do you have 33:03.800 --> 33:05.300 align:start position:10% line:84.66% size:35% pets on Earth? 33:05.300 --> 33:06.333 align:start position:10% line:84.66% size:67.5% >> We have lots of dogs and 33:06.333 --> 33:07.500 align:start position:10% line:84.66% size:12.5% cats. 33:07.500 --> 33:08.733 align:start position:10% line:84.66% size:60% >> I used to have a cat. 33:08.733 --> 33:11.166 align:start position:10% line:84.66% size:75% Your Earth lander landed on it 33:11.166 --> 33:13.666 align:start position:10% line:84.66% size:72.5% and Curiosity killed the cat. 33:13.666 --> 33:15.400 align:start position:10% line:84.66% size:20% [groans] 33:15.400 --> 33:17.433 align:start position:10% line:84.66% size:77.5% But, we continue on in the name 33:17.433 --> 33:19.366 align:start position:10% line:84.66% size:27.5% of science. 33:19.366 --> 33:20.966 align:start position:10% line:84.66% size:80% Let me start up the Van de Graaf 33:20.966 --> 33:23.766 align:start position:10% line:84.66% size:77.5% Generator, and as electrons are 33:23.766 --> 33:25.366 align:start position:10% line:84.66% size:72.5% transferred to the sphere and 33:25.366 --> 33:27.833 align:start position:10% line:84.66% size:67.5% then to the hair, electrons 33:27.833 --> 33:29.466 align:start position:10% line:84.66% size:42.5% repel each other. 33:29.466 --> 33:31.700 align:start position:10% line:84.66% size:47.5% Like charges repel. 33:31.700 --> 33:33.600 align:start position:10% line:84.66% size:77.5% And so the hair stand on end as 33:33.600 --> 33:35.366 align:start position:10% line:84.66% size:55% they repel each other. 33:35.366 --> 33:36.700 align:start position:10% line:84.66% size:80% I have here a grounding rod that 33:36.700 --> 33:37.900 align:start position:10% line:84.66% size:60% will attract some of the 33:37.900 --> 33:39.133 align:start position:10% line:84.66% size:25% electrons. 33:39.133 --> 33:41.333 align:start position:10% line:84.66% size:80% If I remove them, the hair falls 33:41.333 --> 33:46.233 align:start position:10% line:84.66% size:65% back down, as you can see. 33:46.233 --> 33:50.133 align:start position:10% line:84.66% size:77.5% It is the latest style on Mars. 33:50.133 --> 33:53.233 align:start position:10% line:84.66% size:57.5% Well, thank you Fluffy. 33:53.233 --> 33:56.200 align:start position:10% line:84.66% size:25% [applause] 33:58.766 --> 33:59.966 align:start position:10% line:84.66% size:70% As you know, we used to have 33:59.966 --> 34:01.366 align:start position:10% line:84.66% size:77.5% great streams of water on Mars, 34:01.366 --> 34:03.066 align:start position:10% line:84.66% size:77.5% but they are dried up or frozen 34:03.066 --> 34:04.800 align:start position:10% line:84.66% size:10% now. 34:04.800 --> 34:06.233 align:start position:10% line:84.66% size:80% We once thought perhaps we would 34:06.233 --> 34:07.500 align:start position:10% line:84.66% size:62.5% use the water to transmit 34:07.500 --> 34:08.833 align:start position:10% line:84.66% size:30% electricity. 34:08.833 --> 34:10.400 align:start position:10% line:84.66% size:70% Yes, water can interact with 34:10.400 --> 34:11.733 align:start position:10% line:84.66% size:40% electric charge. 34:11.733 --> 34:14.133 align:start position:10% line:84.66% size:80% I will demonstrate this for you. 34:14.133 --> 34:16.633 align:start position:10% line:84.66% size:77.5% I have here some Martian water. 34:16.633 --> 34:18.133 align:start position:10% line:84.66% size:75% It is identical to Earth water 34:18.133 --> 34:20.000 align:start position:10% line:84.66% size:72.5% in composition except for the 34:20.000 --> 34:23.366 align:start position:10% line:84.66% size:65% addition of food coloring. 34:23.366 --> 34:25.333 align:start position:10% line:84.66% size:75% I have here an insulating rod. 34:25.333 --> 34:27.233 align:start position:10% line:84.66% size:77.5% I will charge up the insulating 34:27.233 --> 34:30.500 align:start position:10% line:84.66% size:75% rod by rubbing it with the fur 34:30.500 --> 34:32.266 align:start position:10% line:84.66% size:57.5% of this Martian marmot. 34:32.266 --> 34:33.866 align:start position:10% line:84.66% size:75% Now, I will bring the rod near 34:33.866 --> 34:35.633 align:start position:10% line:84.66% size:72.5% to the water, and we will see 34:35.633 --> 34:38.666 align:start position:10% line:84.66% size:32.5% what happens. 34:38.666 --> 34:40.300 align:start position:10% line:84.66% size:15% Ready? 34:40.300 --> 34:42.633 align:start position:10% line:84.66% size:15% Ahhhh! 34:42.633 --> 34:46.566 align:start position:10% line:84.66% size:75% Now let us try the other side. 34:46.566 --> 34:48.433 align:start position:10% line:84.66% size:77.5% Transferring electrons onto the 34:48.433 --> 34:50.266 align:start position:10% line:84.66% size:75% rod, and then I bring it near, 34:50.266 --> 34:51.533 align:start position:10% line:84.66% size:70% but not touching, the water. 34:51.533 --> 34:53.266 align:start position:10% line:84.66% size:12.5% Ahhh. 34:53.266 --> 34:54.933 align:start position:10% line:84.66% size:50% And it is deflected. 34:54.933 --> 34:57.266 align:start position:10% line:84.66% size:25% [applause] 35:00.633 --> 35:02.800 align:start position:10% line:84.66% size:65% Water can have other uses. 35:02.800 --> 35:04.766 align:start position:10% line:84.66% size:77.5% For example, in rocket science. 35:04.766 --> 35:06.100 align:start position:10% line:84.66% size:70% Yes, we enjoy rocket science 35:06.100 --> 35:07.233 align:start position:10% line:84.66% size:32.5% here in Mars. 35:07.233 --> 35:09.066 align:start position:10% line:84.66% size:80% Professor Sprott, do know how to 35:09.066 --> 35:11.633 align:start position:10% line:84.66% size:70% put a Martian baby to sleep? 35:11.633 --> 35:13.366 align:start position:10% line:84.66% size:65% >> No, how do you do that? 35:13.366 --> 35:14.800 align:start position:10% line:84.66% size:37.5% >> You rock it. 35:14.800 --> 35:17.533 align:start position:10% line:84.66% size:25% [laughter] 35:17.533 --> 35:19.566 align:start position:10% line:84.66% size:77.5% Many of our rocket use hydrogen 35:19.566 --> 35:21.466 align:start position:10% line:84.66% size:80% and oxygen as their propellants. 35:21.466 --> 35:23.000 align:start position:10% line:84.66% size:70% We can get these from water. 35:23.000 --> 35:24.900 align:start position:10% line:84.66% size:75% Yes, does anyone know what the 35:24.900 --> 35:26.866 align:start position:10% line:84.66% size:75% chemical formula for water is? 35:26.866 --> 35:28.433 align:start position:10% line:84.66% size:52.5% Please, shout it out. 35:28.433 --> 35:29.533 align:start position:10% line:84.66% size:32.5% >> Hydrogen-- 35:29.533 --> 35:30.700 align:start position:10% line:84.66% size:27.5% >> Ah, H2O. 35:30.700 --> 35:31.966 align:start position:10% line:84.66% size:40% That is correct. 35:31.966 --> 35:33.800 align:start position:10% line:84.66% size:80% Every molecule of water contains 35:33.800 --> 35:35.833 align:start position:10% line:84.66% size:72.5% two atoms of hydrogen and one 35:35.833 --> 35:37.633 align:start position:10% line:84.66% size:37.5% atom of oxygen. 35:37.633 --> 35:39.200 align:start position:10% line:84.66% size:67.5% We have a device here which 35:39.200 --> 35:41.366 align:start position:10% line:84.66% size:55% performs electrolysis. 35:41.366 --> 35:43.400 align:start position:10% line:84.66% size:77.5% A current is run through water, 35:43.400 --> 35:44.833 align:start position:10% line:84.66% size:77.5% splitting it into it's hydrogen 35:44.833 --> 35:46.166 align:start position:10% line:84.66% size:27.5% and oxygen. 35:46.166 --> 35:47.366 align:start position:10% line:84.66% size:67.5% We have arranged it so that 35:47.366 --> 35:48.700 align:start position:10% line:84.66% size:70% hydrogen is captured here on 35:48.700 --> 35:50.000 align:start position:10% line:84.66% size:80% your left, and the oxygen on the 35:50.000 --> 35:51.100 align:start position:10% line:84.66% size:15% right. 35:51.100 --> 35:52.466 align:start position:10% line:84.66% size:77.5% There is twice as much hydrogen 35:52.466 --> 35:53.833 align:start position:10% line:84.66% size:75% because there are two atoms of 35:53.833 --> 35:55.366 align:start position:10% line:84.66% size:75% hydrogen for every one atom of 35:55.366 --> 35:57.266 align:start position:10% line:84.66% size:17.5% oxygen. 35:57.266 --> 35:59.600 align:start position:10% line:84.66% size:70% How can we test and be sure? 35:59.600 --> 36:00.966 align:start position:10% line:84.66% size:57.5% What is a good test for 36:00.966 --> 36:02.466 align:start position:10% line:84.66% size:22.5% hydrogen? 36:02.466 --> 36:04.866 align:start position:10% line:84.66% size:25% Any ideas? 36:04.866 --> 36:06.400 align:start position:10% line:84.66% size:50% Shout it out please. 36:06.400 --> 36:07.466 align:start position:10% line:84.66% size:60% Clever ideas for testing 36:07.466 --> 36:09.833 align:start position:10% line:84.66% size:22.5% hydrogen? 36:09.833 --> 36:11.200 align:start position:10% line:84.66% size:12.5% Fire! 36:11.200 --> 36:13.466 align:start position:10% line:84.66% size:60% You Martians are clever. 36:13.466 --> 36:15.933 align:start position:10% line:84.66% size:72.5% Yes, we will test by fire for 36:15.933 --> 36:19.600 align:start position:10% line:84.66% size:65% hydrogen, and then oxygen. 36:19.600 --> 36:22.733 align:start position:10% line:84.66% size:70% I will start by lighting two 36:22.733 --> 36:25.766 align:start position:10% line:84.66% size:77.5% candles and we will use them in 36:25.766 --> 36:27.733 align:start position:10% line:84.66% size:25% our tests. 36:27.733 --> 36:30.200 align:start position:10% line:84.66% size:80% Now the hydrogen is lighter than 36:30.200 --> 36:33.233 align:start position:10% line:84.66% size:77.5% air so what I will so is take a 36:33.233 --> 36:36.300 align:start position:10% line:84.66% size:75% vessel and hold it upside down 36:36.300 --> 36:41.200 align:start position:10% line:84.66% size:75% over the hydrogen, release the 36:41.200 --> 36:42.800 align:start position:10% line:84.66% size:72.5% hydrogen, and capture it into 36:42.800 --> 36:44.300 align:start position:10% line:84.66% size:30% this vessel. 36:44.300 --> 36:45.666 align:start position:10% line:84.66% size:70% Then I will bring the candle 36:45.666 --> 36:47.033 align:start position:10% line:84.66% size:65% near, and we will see what 36:47.033 --> 36:49.133 align:start position:10% line:84.66% size:20% happens. 36:49.133 --> 36:52.233 align:start position:10% line:84.66% size:57.5% Releasing the hydrogen! 36:52.233 --> 36:53.933 align:start position:10% line:84.66% size:75% Now this vessel should be full 36:53.933 --> 36:55.366 align:start position:10% line:84.66% size:30% of hydrogen. 36:55.366 --> 36:57.066 align:start position:10% line:84.66% size:35% And the flame. 36:57.066 --> 36:58.866 align:start position:10% line:84.66% size:27.5% [small pop] 36:58.866 --> 37:00.666 align:start position:10% line:84.66% size:25% [applause] 37:00.666 --> 37:02.033 align:start position:10% line:84.66% size:45% A small explosion! 37:02.033 --> 37:03.933 align:start position:10% line:84.66% size:17.5% Indeed! 37:03.933 --> 37:05.633 align:start position:10% line:84.66% size:80% We had hydrogen, now to test for 37:05.633 --> 37:07.200 align:start position:10% line:84.66% size:17.5% oxygen. 37:07.200 --> 37:09.233 align:start position:10% line:84.66% size:70% Oxygen aids in combustion so 37:09.233 --> 37:10.833 align:start position:10% line:84.66% size:67.5% what I will do is take this 37:10.833 --> 37:13.133 align:start position:10% line:84.66% size:77.5% splint of wood and I will begin 37:13.133 --> 37:14.866 align:start position:10% line:84.66% size:27.5% to burn it. 37:14.866 --> 37:16.400 align:start position:10% line:84.66% size:62.5% Once it has some nice red 37:16.400 --> 37:18.200 align:start position:10% line:84.66% size:67.5% embers, I will blow out the 37:18.200 --> 37:19.833 align:start position:10% line:84.66% size:15% flame. 37:19.833 --> 37:22.533 align:start position:10% line:84.66% size:80% Then I will bring it near to the 37:22.533 --> 37:24.733 align:start position:10% line:84.66% size:70% oxygen and expose it to pure 37:24.733 --> 37:26.033 align:start position:10% line:84.66% size:17.5% oxygen. 37:26.033 --> 37:28.933 align:start position:10% line:84.66% size:62.5% We will see what happens. 37:28.933 --> 37:30.866 align:start position:10% line:84.66% size:50% This is now burning. 37:30.866 --> 37:34.033 align:start position:10% line:84.66% size:67.5% Then I will blow it out and 37:34.033 --> 37:37.533 align:start position:10% line:84.66% size:42.5% expose it oxygen. 37:37.533 --> 37:40.066 align:start position:10% line:84.66% size:65% Make sure it is out fully. 37:40.066 --> 37:43.866 align:start position:10% line:84.66% size:30% Then, ahhhh! 37:43.866 --> 37:46.866 align:start position:10% line:84.66% size:25% [applause] 37:46.866 --> 37:48.900 align:start position:10% line:84.66% size:80% The flame has been re-ignited by 37:48.900 --> 37:53.333 align:start position:10% line:84.66% size:60% exposure to pure oxygen. 37:53.333 --> 37:55.733 align:start position:10% line:84.66% size:75% Well, Professor Sprott, I must 37:55.733 --> 37:57.000 align:start position:10% line:84.66% size:55% go and ensure that our 37:57.000 --> 37:59.033 align:start position:10% line:84.66% size:72.5% generators are still running. 37:59.033 --> 38:00.666 align:start position:10% line:84.66% size:60% Thank you for your time. 38:00.666 --> 38:01.866 align:start position:10% line:84.66% size:60% Please say hello to YOUR 38:01.866 --> 38:04.100 align:start position:10% line:84.66% size:80% secretary of energy, Steven Chu, 38:04.100 --> 38:06.133 align:start position:10% line:84.66% size:80% a Nobel Prize winning physicist! 38:06.133 --> 38:08.566 align:start position:10% line:84.66% size:20% Goodbye. 38:08.566 --> 38:10.833 align:start position:10% line:84.66% size:25% [applause] 38:14.200 --> 38:15.600 align:start position:10% line:84.66% size:80% >> Professor Sprott, do you know 38:15.600 --> 38:16.966 align:start position:10% line:84.66% size:67.5% what one magnet said to the 38:16.966 --> 38:18.166 align:start position:10% line:84.66% size:32.5% other magnet? 38:18.166 --> 38:19.333 align:start position:10% line:84.66% size:75% >> No, what did one magnet say 38:19.333 --> 38:20.433 align:start position:10% line:84.66% size:32.5% to the other? 38:20.433 --> 38:22.000 align:start position:10% line:84.66% size:75% >> I find you very attractive. 38:22.000 --> 38:23.133 align:start position:10% line:84.66% size:25% [laughter] 38:23.133 --> 38:24.500 align:start position:10% line:84.66% size:75% So anyhow, magnets are another 38:24.500 --> 38:26.433 align:start position:10% line:84.66% size:65% area of classical physics. 38:26.433 --> 38:28.200 align:start position:10% line:84.66% size:75% We here on Mars have developed 38:28.200 --> 38:29.500 align:start position:10% line:84.66% size:60% the very first magnetic, 38:29.500 --> 38:31.033 align:start position:10% line:84.66% size:40% levitated train. 38:31.033 --> 38:32.233 align:start position:10% line:84.66% size:55% Although, it was quite 38:32.233 --> 38:33.400 align:start position:10% line:84.66% size:80% unsuccessful because of our weak 38:33.400 --> 38:34.433 align:start position:10% line:84.66% size:20% gravity. 38:34.433 --> 38:35.533 align:start position:10% line:84.66% size:75% It just sort of floated off of 38:35.533 --> 38:36.766 align:start position:10% line:84.66% size:27.5% the tracks. 38:36.766 --> 38:38.033 align:start position:10% line:84.66% size:70% Possibly there is a favorite 38:38.033 --> 38:39.333 align:start position:10% line:84.66% size:67.5% magnetism demonstration you 38:39.333 --> 38:40.533 align:start position:10% line:84.66% size:40% could do for us. 38:40.533 --> 38:41.733 align:start position:10% line:84.66% size:45% >> Oh yes, indeed. 38:41.733 --> 38:43.100 align:start position:10% line:84.66% size:72.5% Magnetism and electricity are 38:43.100 --> 38:44.533 align:start position:10% line:84.66% size:52.5% very closely related. 38:44.533 --> 38:46.366 align:start position:10% line:84.66% size:65% In fact, one way to make a 38:46.366 --> 38:48.133 align:start position:10% line:84.66% size:80% strong magnetic field is with an 38:48.133 --> 38:49.766 align:start position:10% line:84.66% size:42.5% electric current. 38:49.766 --> 38:52.066 align:start position:10% line:84.66% size:62.5% Here I have a bar of iron 38:52.066 --> 38:53.333 align:start position:10% line:84.66% size:72.5% surrounded by several hundred 38:53.333 --> 38:54.766 align:start position:10% line:84.66% size:75% turns of copper wire, and it's 38:54.766 --> 38:56.000 align:start position:10% line:84.66% size:80% plugged into the wall back here. 38:56.000 --> 38:57.133 align:start position:10% line:84.66% size:80% In a moment I'm going to turn it 38:57.133 --> 38:59.000 align:start position:10% line:84.66% size:7.5% on. 38:59.000 --> 39:01.100 align:start position:10% line:84.66% size:72.5% Here I have an aluminum ring. 39:01.100 --> 39:02.633 align:start position:10% line:84.66% size:62.5% You know, aluminum is not 39:02.633 --> 39:04.433 align:start position:10% line:84.66% size:72.5% normally a magnetic material. 39:04.433 --> 39:05.733 align:start position:10% line:84.66% size:72.5% Here I have a magnet and it's 39:05.733 --> 39:06.933 align:start position:10% line:84.66% size:67.5% not at all attracted to the 39:06.933 --> 39:08.066 align:start position:10% line:84.66% size:17.5% magnet. 39:08.066 --> 39:09.500 align:start position:10% line:84.66% size:65% To prove it's a magnet, it 39:09.500 --> 39:11.233 align:start position:10% line:84.66% size:65% easily picks up the nails. 39:11.233 --> 39:13.200 align:start position:10% line:84.66% size:77.5% However, when I lower this ring 39:13.200 --> 39:15.066 align:start position:10% line:84.66% size:77.5% down over the electromagnet and 39:15.066 --> 39:17.033 align:start position:10% line:84.66% size:77.5% turn it on, that will induce an 39:17.033 --> 39:19.400 align:start position:10% line:84.66% size:72.5% electric current in the ring. 39:19.400 --> 39:21.766 align:start position:10% line:84.66% size:77.5% That will make this momentarily 39:21.766 --> 39:23.066 align:start position:10% line:84.66% size:22.5% magnetic. 39:23.066 --> 39:24.300 align:start position:10% line:84.66% size:80% Then this magnet will in fact be 39:24.300 --> 39:26.533 align:start position:10% line:84.66% size:60% repelled by this magnet. 39:26.533 --> 39:30.200 align:start position:10% line:84.66% size:37.5% Let's try that. 39:30.200 --> 39:31.766 align:start position:10% line:84.66% size:25% [applause] 39:31.766 --> 39:33.033 align:start position:10% line:84.66% size:55% That went pretty fast. 39:33.033 --> 39:35.333 align:start position:10% line:84.66% size:45% Let's do it again. 39:35.333 --> 39:36.600 align:start position:10% line:84.66% size:77.5% Okay, now you would like to see 39:36.600 --> 39:38.000 align:start position:10% line:84.66% size:55% it go a little higher? 39:38.000 --> 39:39.700 align:start position:10% line:84.66% size:20% >> Yeah! 39:39.700 --> 39:40.933 align:start position:10% line:84.66% size:55% >> Everyone says that. 39:40.933 --> 39:43.066 align:start position:10% line:84.66% size:42.5% I don't know why. 39:43.066 --> 39:44.333 align:start position:10% line:84.66% size:50% Here's an iron pipe. 39:44.333 --> 39:46.033 align:start position:10% line:84.66% size:75% That concentrates the magnetic 39:46.033 --> 39:47.533 align:start position:10% line:84.66% size:80% field and makes it go up higher. 39:47.533 --> 39:48.833 align:start position:10% line:84.66% size:42.5% Let's try it now. 39:48.833 --> 39:51.900 align:start position:10% line:84.66% size:25% [applause] 39:55.300 --> 39:56.466 align:start position:10% line:84.66% size:75% There's another way to make it 39:56.466 --> 39:57.866 align:start position:10% line:84.66% size:20% go high. 39:57.866 --> 39:59.033 align:start position:10% line:84.66% size:65% I can put the ring in this 39:59.033 --> 40:00.366 align:start position:10% line:84.66% size:80% little glass dish and I can pour 40:00.366 --> 40:02.133 align:start position:10% line:84.66% size:72.5% some liquid nitrogen over it. 40:02.133 --> 40:03.800 align:start position:10% line:84.66% size:75% This will give you a chance to 40:03.800 --> 40:06.166 align:start position:10% line:84.66% size:70% observe the liquid nitrogen. 40:06.166 --> 40:07.800 align:start position:10% line:84.66% size:67.5% You'll notice it's boiling. 40:07.800 --> 40:10.133 align:start position:10% line:84.66% size:75% It looks a little like boiling 40:10.133 --> 40:11.333 align:start position:10% line:84.66% size:50% water, but it's not. 40:11.333 --> 40:12.633 align:start position:10% line:84.66% size:35% It's nitrogen. 40:12.633 --> 40:14.900 align:start position:10% line:84.66% size:75% It's boiling because the glass 40:14.900 --> 40:16.233 align:start position:10% line:84.66% size:75% dish and the aluminum ring are 40:16.233 --> 40:17.966 align:start position:10% line:84.66% size:67.5% much warmer than the liquid 40:17.966 --> 40:19.133 align:start position:10% line:84.66% size:22.5% nitrogen. 40:19.133 --> 40:20.566 align:start position:10% line:84.66% size:80% Remember, 321 degrees below zero 40:20.566 --> 40:22.500 align:start position:10% line:84.66% size:27.5% Fahrenheit. 40:22.500 --> 40:23.866 align:start position:10% line:84.66% size:67.5% That causes the nitrogen to 40:23.866 --> 40:25.266 align:start position:10% line:84.66% size:12.5% boil. 40:25.266 --> 40:27.333 align:start position:10% line:84.66% size:75% But in a little while the ring 40:27.333 --> 40:29.333 align:start position:10% line:84.66% size:75% and the dish will cool down to 40:29.333 --> 40:30.533 align:start position:10% line:84.66% size:77.5% the very low temperature of the 40:30.533 --> 40:31.800 align:start position:10% line:84.66% size:67.5% liquid and the boiling will 40:31.800 --> 40:33.233 align:start position:10% line:84.66% size:12.5% stop. 40:33.233 --> 40:34.366 align:start position:10% line:84.66% size:70% At that time I'll be able to 40:34.366 --> 40:35.700 align:start position:10% line:84.66% size:40% remove the ring. 40:35.700 --> 40:37.266 align:start position:10% line:84.66% size:80% It turns out that aluminum, like 40:37.266 --> 40:38.900 align:start position:10% line:84.66% size:72.5% most metals, is a much better 40:38.900 --> 40:40.533 align:start position:10% line:84.66% size:72.5% conductor of electricity when 40:40.533 --> 40:41.900 align:start position:10% line:84.66% size:80% it's cold than when it's at room 40:41.900 --> 40:43.433 align:start position:10% line:84.66% size:30% temperature. 40:43.433 --> 40:44.700 align:start position:10% line:84.66% size:70% In fact, aluminum is about a 40:44.700 --> 40:46.333 align:start position:10% line:84.66% size:77.5% seven times better conductor of 40:46.333 --> 40:47.966 align:start position:10% line:84.66% size:75% electricity at the temperature 40:47.966 --> 40:49.733 align:start position:10% line:84.66% size:47.5% of liquid nitrogen. 40:49.733 --> 40:51.066 align:start position:10% line:84.66% size:70% You would expect the induced 40:51.066 --> 40:52.700 align:start position:10% line:84.66% size:70% current to be larger and the 40:52.700 --> 40:55.033 align:start position:10% line:84.66% size:70% magnetic force to be larger. 40:55.033 --> 40:57.433 align:start position:10% line:84.66% size:77.5% It's just about stopped boiling 40:57.433 --> 40:58.966 align:start position:10% line:84.66% size:70% so I can now take it out and 40:58.966 --> 41:00.666 align:start position:10% line:84.66% size:72.5% repeat the demonstration with 41:00.666 --> 41:02.100 align:start position:10% line:84.66% size:35% the cold ring. 41:02.100 --> 41:05.166 align:start position:10% line:84.66% size:25% [applause] 41:05.166 --> 41:06.233 align:start position:10% line:84.66% size:65% Would you like to see that 41:06.233 --> 41:07.566 align:start position:10% line:84.66% size:15% again? 41:07.566 --> 41:10.933 align:start position:10% line:84.66% size:20% >> Yeah. 41:10.933 --> 41:14.333 align:start position:10% line:84.66% size:7.5% ♪ ♪ 41:14.333 --> 41:15.800 align:start position:10% line:84.66% size:70% Okay, I see you Martians are 41:15.800 --> 41:17.500 align:start position:10% line:84.66% size:40% good scientists. 41:17.500 --> 41:18.933 align:start position:10% line:84.66% size:77.5% You like to do experiments, and 41:18.933 --> 41:20.700 align:start position:10% line:84.66% size:77.5% that's the mark of a scientist. 41:20.700 --> 41:23.200 align:start position:10% line:84.66% size:77.5% Let's try it with the cold ring 41:23.200 --> 41:25.100 align:start position:10% line:84.66% size:45% and the iron core. 41:25.100 --> 41:27.366 align:start position:10% line:84.66% size:25% [applause] 41:37.400 --> 41:39.100 align:start position:10% line:84.66% size:27.5% >> Salvete! 41:39.100 --> 41:41.233 align:start position:10% line:84.66% size:55% Salve clintu Sprottus! 41:41.233 --> 41:44.000 align:start position:10% line:84.66% size:80% Meus nomen Mars est, Deum Belli. 41:44.000 --> 41:45.566 align:start position:10% line:84.66% size:32.5% Quomodo sunt? 41:45.566 --> 41:46.700 align:start position:10% line:84.66% size:72.5% >> Wait a minute, that sounds 41:46.700 --> 41:47.866 align:start position:10% line:84.66% size:27.5% like Latin. 41:47.866 --> 41:48.900 align:start position:10% line:84.66% size:62.5% >> Oh, you speak Martian. 41:48.900 --> 41:49.900 align:start position:10% line:84.66% size:37.5% That was Latin. 41:49.900 --> 41:50.966 align:start position:10% line:84.66% size:72.5% I thought all Earthlings knew 41:50.966 --> 41:52.033 align:start position:10% line:84.66% size:15% Latin. 41:52.033 --> 41:53.033 align:start position:10% line:84.66% size:75% >> No, we haven't spoken Latin 41:53.033 --> 41:54.233 align:start position:10% line:84.66% size:50% in a thousand years. 41:54.233 --> 41:55.433 align:start position:10% line:84.66% size:62.5% >> Now I just feel silly. 41:55.433 --> 41:56.733 align:start position:10% line:84.66% size:77.5% >> You look a little silly, but 41:56.733 --> 41:58.533 align:start position:10% line:84.66% size:52.5% I'm glad you're here. 41:58.533 --> 42:00.666 align:start position:10% line:84.66% size:75% >> I guess I don't need these. 42:00.666 --> 42:01.700 align:start position:10% line:84.66% size:45% My name is Blaine. 42:01.700 --> 42:02.933 align:start position:10% line:84.66% size:77.5% I'm the chief scientist for the 42:02.933 --> 42:04.333 align:start position:10% line:84.66% size:75% Martian Department of Defense. 42:04.333 --> 42:05.733 align:start position:10% line:84.66% size:77.5% A long time ago I was sent on a 42:05.733 --> 42:07.500 align:start position:10% line:84.66% size:80% reconnaissance mission to Earth. 42:07.500 --> 42:08.833 align:start position:10% line:84.66% size:70% Due to some poorly made crop 42:08.833 --> 42:10.100 align:start position:10% line:84.66% size:72.5% circles, we took a wrong turn 42:10.100 --> 42:11.433 align:start position:10% line:84.66% size:77.5% and crash-landed on a continent 42:11.433 --> 42:12.766 align:start position:10% line:84.66% size:65% known as Europe during the 42:12.766 --> 42:14.200 align:start position:10% line:84.66% size:67.5% height of the Roman Empire. 42:14.200 --> 42:15.633 align:start position:10% line:84.66% size:72.5% Luckily we had enough Martian 42:15.633 --> 42:17.366 align:start position:10% line:84.66% size:77.5% Dew to sustain us for the trip, 42:17.366 --> 42:18.433 align:start position:10% line:84.66% size:67.5% and we shared some with the 42:18.433 --> 42:19.666 align:start position:10% line:84.66% size:47.5% locals that we met. 42:19.666 --> 42:20.800 align:start position:10% line:84.66% size:72.5% We found a really interesting 42:20.800 --> 42:21.966 align:start position:10% line:84.66% size:55% effect on them though. 42:21.966 --> 42:23.233 align:start position:10% line:84.66% size:70% You see, it made them really 42:23.233 --> 42:24.366 align:start position:10% line:84.66% size:75% strong and gave them increased 42:24.366 --> 42:25.433 align:start position:10% line:84.66% size:25% endurance. 42:25.433 --> 42:26.600 align:start position:10% line:84.66% size:60% Using Martian Dew, Roman 42:26.600 --> 42:27.800 align:start position:10% line:84.66% size:72.5% soldiers were able to conquer 42:27.800 --> 42:29.000 align:start position:10% line:84.66% size:60% much of the known world. 42:29.000 --> 42:30.033 align:start position:10% line:84.66% size:80% Since I was the one that brought 42:30.033 --> 42:31.100 align:start position:10% line:84.66% size:40% it to them, they 42:31.100 --> 42:32.133 align:start position:10% line:84.66% size:80% began to worship me as Mars, the 42:32.133 --> 42:33.433 align:start position:10% line:84.66% size:27.5% God of War. 42:33.433 --> 42:34.533 align:start position:10% line:84.66% size:80% Of course, I was in no condition 42:34.533 --> 42:36.600 align:start position:10% line:84.66% size:40% to correct them. 42:36.600 --> 42:37.633 align:start position:10% line:84.66% size:67.5% Humans have since developed 42:37.633 --> 42:38.766 align:start position:10% line:84.66% size:47.5% their own compound. 42:38.766 --> 42:39.933 align:start position:10% line:84.66% size:65% They call it Mountain Dew. 42:39.933 --> 42:41.200 align:start position:10% line:84.66% size:70% It's not quite as effective. 42:41.200 --> 42:42.666 align:start position:10% line:84.66% size:70% It lacks one key ingredient, 42:42.666 --> 42:44.100 align:start position:10% line:84.66% size:57.5% stored magnetic energy. 42:44.100 --> 42:45.200 align:start position:10% line:84.66% size:80% Would you all like to see how we 42:45.200 --> 42:46.300 align:start position:10% line:84.66% size:75% put that ingredient in here on 42:46.300 --> 42:47.333 align:start position:10% line:84.66% size:12.5% Mars? 42:47.333 --> 42:48.433 align:start position:10% line:84.66% size:20% >> Yeah. 42:48.433 --> 42:49.533 align:start position:10% line:84.66% size:22.5% >> Great. 42:49.533 --> 42:50.533 align:start position:10% line:84.66% size:72.5% We have one of the devices at 42:50.533 --> 42:51.800 align:start position:10% line:84.66% size:70% the very end of the assembly 42:51.800 --> 42:52.833 align:start position:10% line:84.66% size:12.5% line. 42:52.833 --> 42:53.833 align:start position:10% line:84.66% size:70% So a full can of Martian Dew 42:53.833 --> 42:55.266 align:start position:10% line:84.66% size:75% would be put into this device. 42:55.266 --> 42:56.333 align:start position:10% line:84.66% size:70% I have here an empty can and 42:56.333 --> 42:57.433 align:start position:10% line:84.66% size:72.5% we've hollowed out the bottom 42:57.433 --> 42:58.433 align:start position:10% line:84.66% size:65% for a little more dramatic 42:58.433 --> 42:59.700 align:start position:10% line:84.66% size:17.5% effect. 42:59.700 --> 43:01.066 align:start position:10% line:84.66% size:80% Now you'll see this large orange 43:01.066 --> 43:02.200 align:start position:10% line:84.66% size:27.5% block here. 43:02.200 --> 43:03.300 align:start position:10% line:84.66% size:57.5% This is what's called a 43:03.300 --> 43:04.366 align:start position:10% line:84.66% size:25% capacitor. 43:04.366 --> 43:05.466 align:start position:10% line:84.66% size:77.5% It's like a really big battery, 43:05.466 --> 43:07.300 align:start position:10% line:84.66% size:75% but it discharges all at once. 43:07.300 --> 43:08.500 align:start position:10% line:84.66% size:70% When I let go of this button 43:08.500 --> 43:10.033 align:start position:10% line:84.66% size:77.5% 5000 volts of potential will be 43:10.033 --> 43:11.666 align:start position:10% line:84.66% size:72.5% released, and that current is 43:11.666 --> 43:13.000 align:start position:10% line:84.66% size:80% going to run through this device 43:13.000 --> 43:14.800 align:start position:10% line:84.66% size:80% where these copper windings are. 43:14.800 --> 43:15.933 align:start position:10% line:84.66% size:60% As it goes through those 43:15.933 --> 43:17.200 align:start position:10% line:84.66% size:77.5% windings it's going to create a 43:17.200 --> 43:18.366 align:start position:10% line:84.66% size:55% strong magnetic field. 43:18.366 --> 43:19.400 align:start position:10% line:84.66% size:67.5% That will interact with the 43:19.400 --> 43:20.500 align:start position:10% line:84.66% size:72.5% electric field that's part of 43:20.500 --> 43:21.566 align:start position:10% line:84.66% size:30% the current. 43:21.566 --> 43:22.633 align:start position:10% line:84.66% size:77.5% When these two field's interact 43:22.633 --> 43:23.733 align:start position:10% line:84.66% size:70% with each other, they create 43:23.733 --> 43:24.800 align:start position:10% line:84.66% size:75% something known as the Lorentz 43:24.800 --> 43:26.000 align:start position:10% line:84.66% size:67.5% Force, named after a famous 43:26.000 --> 43:27.266 align:start position:10% line:84.66% size:40% Earth physicist. 43:27.266 --> 43:28.400 align:start position:10% line:84.66% size:72.5% That force is going to act to 43:28.400 --> 43:29.766 align:start position:10% line:84.66% size:52.5% pinch the can inward. 43:29.766 --> 43:30.766 align:start position:10% line:84.66% size:77.5% It's really dramatic and really 43:30.766 --> 43:31.766 align:start position:10% line:84.66% size:12.5% loud. 43:31.766 --> 43:32.933 align:start position:10% line:84.66% size:77.5% So if you're in the front row I 43:32.933 --> 43:35.100 align:start position:10% line:84.66% size:70% suggest you close your ears. 43:35.100 --> 43:37.533 align:start position:10% line:84.66% size:77.5% Here we go, in three, two, one. 43:37.533 --> 43:39.466 align:start position:10% line:84.66% size:25% [can pops] 43:39.466 --> 43:42.333 align:start position:10% line:84.66% size:25% [applause] 43:43.533 --> 43:45.500 align:start position:10% line:84.66% size:57.5% Pretty dramatic, right? 43:45.500 --> 43:46.633 align:start position:10% line:84.66% size:75% You'll notice, it jumped out a 43:46.633 --> 43:47.733 align:start position:10% line:84.66% size:27.5% little bit. 43:47.733 --> 43:48.800 align:start position:10% line:84.66% size:75% I'd like to see if we can make 43:48.800 --> 43:49.866 align:start position:10% line:84.66% size:72.5% it jump a little bit farther. 43:49.866 --> 43:50.966 align:start position:10% line:84.66% size:72.5% I'm going to place the can in 43:50.966 --> 43:52.500 align:start position:10% line:84.66% size:75% just a little bit differently. 43:52.500 --> 43:53.566 align:start position:10% line:84.66% size:72.5% I got this idea from studying 43:53.566 --> 43:54.700 align:start position:10% line:84.66% size:77.5% Naval warships that the US Navy 43:54.700 --> 43:55.900 align:start position:10% line:84.66% size:12.5% uses. 43:55.900 --> 43:56.933 align:start position:10% line:84.66% size:67.5% You see, they have a device 43:56.933 --> 43:58.166 align:start position:10% line:84.66% size:72.5% called a rail gun, which is a 43:58.166 --> 43:59.700 align:start position:10% line:84.66% size:80% really long platform and it used 43:59.700 --> 44:01.066 align:start position:10% line:84.66% size:75% similar electromagnetic energy 44:01.066 --> 44:03.933 align:start position:10% line:84.66% size:77.5% to launch projectiles very far. 44:03.933 --> 44:05.533 align:start position:10% line:84.66% size:77.5% Now, sir, in the blue, it looks 44:05.533 --> 44:06.566 align:start position:10% line:84.66% size:70% like it's going to be coming 44:06.566 --> 44:07.700 align:start position:10% line:84.66% size:32.5% right at you. 44:07.700 --> 44:08.700 align:start position:10% line:84.66% size:10% Yup. 44:08.700 --> 44:09.800 align:start position:10% line:84.66% size:77.5% Everyone else keep your head up 44:09.800 --> 44:10.800 align:start position:10% line:84.66% size:32.5% just in case. 44:10.800 --> 44:13.466 align:start position:10% line:84.66% size:77.5% Here we go, in three, two, one. 44:13.466 --> 44:15.466 align:start position:10% line:84.66% size:25% [can pops] 44:15.466 --> 44:18.200 align:start position:10% line:84.66% size:25% [applause] 44:24.166 --> 44:25.366 align:start position:10% line:84.66% size:72.5% Now of course, had there been 44:25.366 --> 44:26.533 align:start position:10% line:84.66% size:70% Martian Dew in that can, the 44:26.533 --> 44:27.800 align:start position:10% line:84.66% size:77.5% magnetic energy would have been 44:27.800 --> 44:28.966 align:start position:10% line:84.66% size:72.5% stored in there for delicious 44:28.966 --> 44:30.633 align:start position:10% line:84.66% size:37.5% nutrient later. 44:30.633 --> 44:32.033 align:start position:10% line:84.66% size:75% Humans have been experimenting 44:32.033 --> 44:33.366 align:start position:10% line:84.66% size:62.5% with fluids that react to 44:33.366 --> 44:34.866 align:start position:10% line:84.66% size:52.5% magnetic fields also. 44:34.866 --> 44:36.066 align:start position:10% line:84.66% size:77.5% They call them ferrofluids from 44:36.066 --> 44:37.700 align:start position:10% line:84.66% size:70% the Latin word ferrum, which 44:37.700 --> 44:38.800 align:start position:10% line:84.66% size:27.5% means iron. 44:38.800 --> 44:39.800 align:start position:10% line:84.66% size:67.5% I have here an example of a 44:39.800 --> 44:40.833 align:start position:10% line:84.66% size:27.5% ferrofluid. 44:40.833 --> 44:41.866 align:start position:10% line:84.66% size:77.5% It's just a bunch of small iron 44:41.866 --> 44:42.900 align:start position:10% line:84.66% size:55% filings that have been 44:42.900 --> 44:44.133 align:start position:10% line:84.66% size:57.5% emulsified in a liquid. 44:44.133 --> 44:45.133 align:start position:10% line:84.66% size:72.5% You can see it up here on the 44:45.133 --> 44:46.133 align:start position:10% line:84.66% size:17.5% screen. 44:46.133 --> 44:47.366 align:start position:10% line:84.66% size:80% I just looks like a plain liquid 44:47.366 --> 44:48.366 align:start position:10% line:84.66% size:72.5% in a beaker, but as I bring a 44:48.366 --> 44:49.600 align:start position:10% line:84.66% size:77.5% magnet near it, you'll see that 44:49.600 --> 44:50.733 align:start position:10% line:84.66% size:77.5% the fluid will try to along the 44:50.733 --> 44:55.433 align:start position:10% line:84.66% size:52.5% magnetic field lines. 44:55.433 --> 44:56.633 align:start position:10% line:84.66% size:77.5% If I flip the magnet around, it 44:56.633 --> 45:01.200 align:start position:10% line:84.66% size:77.5% will be a little more dramatic. 45:01.200 --> 45:03.600 align:start position:10% line:84.66% size:42.5% Pretty cool, huh? 45:03.600 --> 45:04.800 align:start position:10% line:84.66% size:72.5% Now ferrofluids like this are 45:04.800 --> 45:06.033 align:start position:10% line:84.66% size:70% used in high-tech industrial 45:06.033 --> 45:07.500 align:start position:10% line:84.66% size:72.5% applications, a sort of motor 45:07.500 --> 45:08.800 align:start position:10% line:84.66% size:67.5% oil, especially like in the 45:08.800 --> 45:12.866 align:start position:10% line:84.66% size:47.5% aerospace industry. 45:12.866 --> 45:14.000 align:start position:10% line:84.66% size:75% I have one more experiment I'd 45:14.000 --> 45:15.033 align:start position:10% line:84.66% size:42.5% like to show you. 45:15.033 --> 45:16.066 align:start position:10% line:84.66% size:77.5% Some of you may be thinking, if 45:16.066 --> 45:17.133 align:start position:10% line:84.66% size:72.5% you have a floating train and 45:17.133 --> 45:18.533 align:start position:10% line:84.66% size:80% you need to get it to stop, what 45:18.533 --> 45:20.233 align:start position:10% line:84.66% size:25% do you do? 45:20.233 --> 45:21.266 align:start position:10% line:84.66% size:75% There's no friction to use for 45:21.266 --> 45:22.933 align:start position:10% line:84.66% size:40% breaking, right? 45:22.933 --> 45:24.066 align:start position:10% line:84.66% size:75% We can use magnetic forces for 45:24.066 --> 45:25.266 align:start position:10% line:84.66% size:25% that also. 45:25.266 --> 45:26.533 align:start position:10% line:84.66% size:77.5% I have here another magnet, and 45:26.533 --> 45:27.833 align:start position:10% line:84.66% size:67.5% here we have a large copper 45:27.833 --> 45:28.966 align:start position:10% line:84.66% size:15% plate. 45:28.966 --> 45:30.133 align:start position:10% line:84.66% size:75% Copper is a great conductor of 45:30.133 --> 45:31.233 align:start position:10% line:84.66% size:30% electricity. 45:31.233 --> 45:32.633 align:start position:10% line:84.66% size:80% As you'll see, whenever a magnet 45:32.633 --> 45:34.066 align:start position:10% line:84.66% size:70% is dropping towards a copper 45:34.066 --> 45:35.133 align:start position:10% line:84.66% size:70% plate it creates a change in 45:35.133 --> 45:36.133 align:start position:10% line:84.66% size:12.5% flux. 45:36.133 --> 45:37.133 align:start position:10% line:84.66% size:77.5% It will make something known as 45:37.133 --> 45:38.533 align:start position:10% line:84.66% size:77.5% eddy currents in the conductor. 45:38.533 --> 45:39.700 align:start position:10% line:84.66% size:77.5% Those eddy currents will create 45:39.700 --> 45:40.833 align:start position:10% line:84.66% size:77.5% a force that will try to oppose 45:40.833 --> 45:42.300 align:start position:10% line:84.66% size:50% that change in flux. 45:42.300 --> 45:43.733 align:start position:10% line:84.66% size:75% What that means is it will try 45:43.733 --> 45:45.233 align:start position:10% line:84.66% size:80% to stop the magnet from falling. 45:45.233 --> 45:46.333 align:start position:10% line:84.66% size:65% You'll see it falls pretty 45:46.333 --> 45:47.400 align:start position:10% line:84.66% size:65% readily under the force of 45:47.400 --> 45:48.733 align:start position:10% line:84.66% size:80% gravity, but as we drop it above 45:48.733 --> 45:49.800 align:start position:10% line:84.66% size:75% the plate, it falls a like bit 45:49.800 --> 45:51.500 align:start position:10% line:84.66% size:17.5% slower. 45:51.500 --> 45:53.966 align:start position:10% line:84.66% size:70% It's not so slow that it's a 45:53.966 --> 45:55.900 align:start position:10% line:84.66% size:77.5% huge noticeable effect, but you 45:55.900 --> 45:58.300 align:start position:10% line:84.66% size:77.5% all also learned from Professor 45:58.300 --> 45:59.900 align:start position:10% line:84.66% size:60% Sprott that if we cool a 45:59.900 --> 46:01.200 align:start position:10% line:84.66% size:77.5% conductor down it's much better 46:01.200 --> 46:02.466 align:start position:10% line:84.66% size:35% at conducting. 46:02.466 --> 46:03.566 align:start position:10% line:84.66% size:67.5% So I have here an identical 46:03.566 --> 46:05.066 align:start position:10% line:84.66% size:75% copper plate that we've placed 46:05.066 --> 46:07.933 align:start position:10% line:84.66% size:72.5% in a bath of liquid nitrogen. 46:07.933 --> 46:11.066 align:start position:10% line:84.66% size:80% As you'll see, the eddy currents 46:11.066 --> 46:12.833 align:start position:10% line:84.66% size:57.5% should be a little more 46:12.833 --> 46:14.133 align:start position:10% line:84.66% size:72.5% effective at slowing it down. 46:14.133 --> 46:15.833 align:start position:10% line:84.66% size:45% Let's take a look. 46:15.833 --> 46:17.000 align:start position:10% line:84.66% size:37.5% [oohs and ahhs] 46:17.000 --> 46:18.166 align:start position:10% line:84.66% size:77.5% It takes a little bit longer to 46:18.166 --> 46:19.300 align:start position:10% line:84.66% size:12.5% fall. 46:19.300 --> 46:20.566 align:start position:10% line:84.66% size:72.5% In fact, even just tipping it 46:20.566 --> 46:22.100 align:start position:10% line:84.66% size:60% over takes a lot longer. 46:25.333 --> 46:26.600 align:start position:10% line:84.66% size:80% This is the kind of mechanism we 46:26.600 --> 46:27.966 align:start position:10% line:84.66% size:65% can use to stop the MagLev 46:27.966 --> 46:29.066 align:start position:10% line:84.66% size:15% train. 46:29.066 --> 46:30.400 align:start position:10% line:84.66% size:75% I'm told that on Earth there's 46:30.400 --> 46:31.866 align:start position:10% line:84.66% size:77.5% these great child warriors that 46:31.866 --> 46:33.433 align:start position:10% line:84.66% size:65% will lash together several 46:33.433 --> 46:34.600 align:start position:10% line:84.66% size:22.5% chariots. 46:34.600 --> 46:35.866 align:start position:10% line:84.66% size:72.5% They call such a war device a 46:35.866 --> 46:37.733 align:start position:10% line:84.66% size:37.5% roller coaster. 46:37.733 --> 46:38.933 align:start position:10% line:84.66% size:65% This is the same principle 46:38.933 --> 46:40.100 align:start position:10% line:84.66% size:65% that's used to slow roller 46:40.100 --> 46:41.400 align:start position:10% line:84.66% size:67.5% coasters down at the end of 46:41.400 --> 46:42.500 align:start position:10% line:84.66% size:30% their rides. 46:42.500 --> 46:43.700 align:start position:10% line:84.66% size:72.5% Well, if you'll excuse me, we 46:43.700 --> 46:44.900 align:start position:10% line:84.66% size:77.5% need to go plan our invasion of 46:44.900 --> 46:46.033 align:start position:10% line:84.66% size:80% Venus, but I hope you've learned 46:46.033 --> 46:47.300 align:start position:10% line:84.66% size:60% a little something about 46:47.300 --> 46:49.100 align:start position:10% line:84.66% size:55% magnetic energy today. 46:49.100 --> 46:50.833 align:start position:10% line:84.66% size:25% [applause] 46:53.900 --> 46:55.266 align:start position:10% line:84.66% size:72.5% >> Well, Professor Sprott, do 46:55.266 --> 46:56.666 align:start position:10% line:84.66% size:72.5% you know how many theoretical 46:56.666 --> 46:58.800 align:start position:10% line:84.66% size:65% physicists specializing in 46:58.800 --> 47:00.466 align:start position:10% line:84.66% size:67.5% general relativity it takes 47:00.466 --> 47:02.066 align:start position:10% line:84.66% size:57.5% to change a light bulb? 47:02.066 --> 47:03.400 align:start position:10% line:84.66% size:72.5% >> No, how many does it take? 47:03.400 --> 47:04.500 align:start position:10% line:84.66% size:17.5% >> Two. 47:04.500 --> 47:05.600 align:start position:10% line:84.66% size:75% One to hold the light bulb and 47:05.600 --> 47:06.600 align:start position:10% line:84.66% size:57.5% the other to rotate the 47:06.600 --> 47:07.900 align:start position:10% line:84.66% size:22.5% universe. 47:07.900 --> 47:08.966 align:start position:10% line:84.66% size:25% [laughter] 47:08.966 --> 47:10.100 align:start position:10% line:84.66% size:57.5% Anyhow, speaking of the 47:10.100 --> 47:11.266 align:start position:10% line:84.66% size:80% universe, one thing I do like to 47:11.266 --> 47:12.433 align:start position:10% line:84.66% size:77.5% do when I'm up at the castle at 47:12.433 --> 47:13.633 align:start position:10% line:84.66% size:77.5% Mount Olympus is look up at the 47:13.633 --> 47:14.900 align:start position:10% line:84.66% size:72.5% sky and see all the beautiful 47:14.900 --> 47:16.266 align:start position:10% line:84.66% size:52.5% stars that are there. 47:16.266 --> 47:18.033 align:start position:10% line:84.66% size:67.5% Can you see stars on Earth? 47:18.033 --> 47:20.100 align:start position:10% line:84.66% size:80% >> We sure can, but I've noticed 47:20.100 --> 47:21.333 align:start position:10% line:84.66% size:60% that your stars here are 47:21.333 --> 47:22.433 align:start position:10% line:84.66% size:42.5% especially vivid. 47:22.433 --> 47:23.500 align:start position:10% line:84.66% size:75% I think that's because of your 47:23.500 --> 47:24.900 align:start position:10% line:84.66% size:40% thin atmosphere. 47:24.900 --> 47:26.033 align:start position:10% line:84.66% size:80% On Earth we have to look through 47:26.033 --> 47:27.800 align:start position:10% line:84.66% size:60% a very dense atmosphere. 47:27.800 --> 47:29.000 align:start position:10% line:84.66% size:67.5% Sometimes it's polluted, it 47:29.000 --> 47:30.633 align:start position:10% line:84.66% size:77.5% reflects light from the ground. 47:30.633 --> 47:32.233 align:start position:10% line:84.66% size:67.5% Often it's very hard to see 47:32.233 --> 47:34.000 align:start position:10% line:84.66% size:47.5% stars on the Earth. 47:34.000 --> 47:35.433 align:start position:10% line:84.66% size:80% Our stars also do something that 47:35.433 --> 47:37.600 align:start position:10% line:84.66% size:70% your Martian stars don't do. 47:37.600 --> 47:39.366 align:start position:10% line:84.66% size:57.5% They appear to twinkle. 47:39.366 --> 47:40.633 align:start position:10% line:84.66% size:65% You may not know what that 47:40.633 --> 47:41.900 align:start position:10% line:84.66% size:80% means, but I can show you with a 47:41.900 --> 47:44.200 align:start position:10% line:84.66% size:65% little demonstration here. 47:44.200 --> 47:45.666 align:start position:10% line:84.66% size:50% Here I have a laser. 47:45.666 --> 47:46.733 align:start position:10% line:84.66% size:77.5% I'm going to turn it on and you 47:46.733 --> 47:48.033 align:start position:10% line:84.66% size:70% can see that dot on the wall 47:48.033 --> 47:49.566 align:start position:10% line:84.66% size:65% over there coming from the 47:49.566 --> 47:50.933 align:start position:10% line:84.66% size:15% laser. 47:50.933 --> 47:52.100 align:start position:10% line:84.66% size:75% To prove that it's coming from 47:52.100 --> 47:53.300 align:start position:10% line:84.66% size:67.5% the laser, I can just put a 47:53.300 --> 47:54.800 align:start position:10% line:84.66% size:77.5% little spray here to illuminate 47:54.800 --> 47:56.633 align:start position:10% line:84.66% size:37.5% the laser beam. 47:56.633 --> 47:59.800 align:start position:10% line:84.66% size:65% As you would expect, light 47:59.800 --> 48:01.200 align:start position:10% line:84.66% size:67.5% travels in quite a straight 48:01.200 --> 48:02.566 align:start position:10% line:84.66% size:12.5% line. 48:02.566 --> 48:03.700 align:start position:10% line:84.66% size:67.5% But it turns out it doesn't 48:03.700 --> 48:04.800 align:start position:10% line:84.66% size:75% travel in an absolute straight 48:04.800 --> 48:06.133 align:start position:10% line:84.66% size:12.5% line. 48:06.133 --> 48:07.133 align:start position:10% line:84.66% size:60% When it goes through the 48:07.133 --> 48:08.700 align:start position:10% line:84.66% size:67.5% atmosphere it bends ever so 48:08.700 --> 48:10.033 align:start position:10% line:84.66% size:22.5% slightly. 48:10.033 --> 48:12.000 align:start position:10% line:84.66% size:80% The amount that it bends depends 48:12.000 --> 48:13.266 align:start position:10% line:84.66% size:52.5% on the density of the 48:13.266 --> 48:14.700 align:start position:10% line:84.66% size:77.5% atmosphere, which is determined 48:14.700 --> 48:16.000 align:start position:10% line:84.66% size:62.5% by the temperature of the 48:16.000 --> 48:17.400 align:start position:10% line:84.66% size:27.5% atmosphere. 48:17.400 --> 48:19.433 align:start position:10% line:84.66% size:72.5% If I can do something to warm 48:19.433 --> 48:20.733 align:start position:10% line:84.66% size:80% the air here, I might be able to 48:20.733 --> 48:23.333 align:start position:10% line:84.66% size:80% show you what it looks like when 48:23.333 --> 48:24.833 align:start position:10% line:84.66% size:72.5% we look at the stars from the 48:24.833 --> 48:26.466 align:start position:10% line:84.66% size:57.5% Earth through our dense 48:26.466 --> 48:28.000 align:start position:10% line:84.66% size:27.5% atmosphere. 48:28.000 --> 48:29.300 align:start position:10% line:84.66% size:77.5% I'm going to light this burner, 48:29.300 --> 48:30.400 align:start position:10% line:84.66% size:72.5% remind myself where the laser 48:30.400 --> 48:31.833 align:start position:10% line:84.66% size:75% beam is, then I'm going to put 48:31.833 --> 48:33.066 align:start position:10% line:84.66% size:77.5% the burner underneath the laser 48:33.066 --> 48:34.166 align:start position:10% line:84.66% size:12.5% beam. 48:34.166 --> 48:35.166 align:start position:10% line:84.66% size:80% Look at the dot on the wall over 48:35.166 --> 48:36.800 align:start position:10% line:84.66% size:15% there. 48:36.800 --> 48:38.666 align:start position:10% line:84.66% size:75% [music plays Twinkle, Twinkle] 48:44.833 --> 48:45.900 align:start position:10% line:84.66% size:70% And that's what we mean by a 48:45.900 --> 48:47.733 align:start position:10% line:84.66% size:37.5% twinkling star. 48:47.733 --> 48:49.566 align:start position:10% line:84.66% size:25% [applause] 48:52.600 --> 48:54.066 align:start position:10% line:84.66% size:75% >> Greetings Professor Sprott. 48:54.066 --> 48:55.966 align:start position:10% line:84.66% size:57.5% We welcome you to Mars. 48:55.966 --> 48:57.633 align:start position:10% line:84.66% size:60% >> We are members of the 48:57.633 --> 48:59.500 align:start position:10% line:84.66% size:55% Martian Light Brigade. 48:59.500 --> 49:00.766 align:start position:10% line:84.66% size:45% We have found your 49:00.766 --> 49:01.900 align:start position:10% line:84.66% size:62.5% demonstrations to be most 49:01.900 --> 49:03.366 align:start position:10% line:84.66% size:32.5% illuminating. 49:03.366 --> 49:04.966 align:start position:10% line:84.66% size:25% [laughter] 49:04.966 --> 49:06.366 align:start position:10% line:84.66% size:60% >> It's our job to study 49:06.366 --> 49:08.066 align:start position:10% line:84.66% size:70% how to do things with light! 49:08.066 --> 49:09.633 align:start position:10% line:84.66% size:72.5% We'd like to show some of the 49:09.633 --> 49:11.166 align:start position:10% line:84.66% size:62.5% things we've learned from 49:11.166 --> 49:12.500 align:start position:10% line:84.66% size:47.5% watching your show. 49:12.500 --> 49:13.600 align:start position:10% line:84.66% size:70% The other day I was watching 49:13.600 --> 49:14.700 align:start position:10% line:84.66% size:35% some Earth TV. 49:14.700 --> 49:15.833 align:start position:10% line:84.66% size:80% >> Don't watch too much TV kids. 49:15.833 --> 49:17.533 align:start position:10% line:84.66% size:60% It will rot your brains. 49:17.533 --> 49:18.633 align:start position:10% line:84.66% size:45% >> It's very true. 49:18.633 --> 49:19.800 align:start position:10% line:84.66% size:80% I was just watching a little bit 49:19.800 --> 49:21.366 align:start position:10% line:84.66% size:72.5% of television when I saw some 49:21.366 --> 49:23.433 align:start position:10% line:84.66% size:75% Earth cities at night-time all 49:23.433 --> 49:25.000 align:start position:10% line:84.66% size:77.5% lit up with very bright colors. 49:25.000 --> 49:26.133 align:start position:10% line:84.66% size:70% I noticed that some of these 49:26.133 --> 49:29.666 align:start position:10% line:84.66% size:80% lights were caused by signs with 49:29.666 --> 49:31.500 align:start position:10% line:84.66% size:40% letters on them. 49:31.500 --> 49:32.800 align:start position:10% line:84.66% size:70% I found out that these signs 49:32.800 --> 49:34.633 align:start position:10% line:84.66% size:62.5% where called neon lights. 49:34.633 --> 49:36.666 align:start position:10% line:84.66% size:60% Another word for this is 49:36.666 --> 49:37.900 align:start position:10% line:84.66% size:37.5% Geissler tubes. 49:37.900 --> 49:39.166 align:start position:10% line:84.66% size:70% I wanted to learn more about 49:39.166 --> 49:41.433 align:start position:10% line:84.66% size:42.5% what caused this. 49:41.433 --> 49:42.900 align:start position:10% line:84.66% size:70% We made some to have here on 49:42.900 --> 49:44.033 align:start position:10% line:84.66% size:12.5% Mars. 49:44.033 --> 49:45.300 align:start position:10% line:84.66% size:75% We'd like to show them to you. 49:45.300 --> 49:46.433 align:start position:10% line:84.66% size:70% >> Here we have our Geissler 49:46.433 --> 49:47.500 align:start position:10% line:84.66% size:15% tubes. 49:47.500 --> 49:48.600 align:start position:10% line:84.66% size:75% We just have a series of glass 49:48.600 --> 49:49.766 align:start position:10% line:84.66% size:75% tubes, and each tube is filled 49:49.766 --> 49:50.933 align:start position:10% line:84.66% size:60% with a gas such as neon. 49:50.933 --> 49:52.133 align:start position:10% line:84.66% size:80% What we're going to do is run an 49:52.133 --> 49:53.366 align:start position:10% line:84.66% size:80% electric current through each of 49:53.366 --> 49:54.633 align:start position:10% line:84.66% size:25% the tubes. 49:54.633 --> 49:55.833 align:start position:10% line:84.66% size:72.5% When we do this, the electric 49:55.833 --> 49:57.000 align:start position:10% line:84.66% size:75% current is going to excite the 49:57.000 --> 49:58.166 align:start position:10% line:84.66% size:80% atoms in the gases, causing them 49:58.166 --> 49:59.700 align:start position:10% line:84.66% size:20% to glow. 49:59.700 --> 50:02.866 align:start position:10% line:84.66% size:30% Take a look. 50:05.033 --> 50:07.966 align:start position:10% line:84.66% size:25% [applause] 50:13.466 --> 50:14.633 align:start position:10% line:84.66% size:75% Something else we have learned 50:14.633 --> 50:15.766 align:start position:10% line:84.66% size:75% from studying Earth is that if 50:15.766 --> 50:17.266 align:start position:10% line:84.66% size:75% you look at the sky on a Earth 50:17.266 --> 50:19.033 align:start position:10% line:84.66% size:72.5% you will see that it is blue. 50:19.033 --> 50:20.900 align:start position:10% line:84.66% size:62.5% We wondered, why is this? 50:20.900 --> 50:22.500 align:start position:10% line:84.66% size:75% Why is it that the Earth's sky 50:22.500 --> 50:23.766 align:start position:10% line:84.66% size:20% is blue? 50:23.766 --> 50:25.100 align:start position:10% line:84.66% size:70% It turns out that the sky is 50:25.100 --> 50:26.266 align:start position:10% line:84.66% size:80% blue because of something called 50:26.266 --> 50:28.033 align:start position:10% line:84.66% size:50% Reyleigh scattering. 50:28.033 --> 50:29.500 align:start position:10% line:84.66% size:75% When light from the sun, which 50:29.500 --> 50:31.000 align:start position:10% line:84.66% size:72.5% is white light, or all colors 50:31.000 --> 50:33.200 align:start position:10% line:84.66% size:62.5% combined, when that light 50:33.200 --> 50:34.966 align:start position:10% line:84.66% size:75% strikes the Earth's atmosphere 50:34.966 --> 50:36.300 align:start position:10% line:84.66% size:70% light that is more yellow in 50:36.300 --> 50:37.666 align:start position:10% line:84.66% size:72.5% color passes straight through 50:37.666 --> 50:39.100 align:start position:10% line:84.66% size:75% the atmosphere and come to the 50:39.100 --> 50:40.600 align:start position:10% line:84.66% size:70% ground whereas light that is 50:40.600 --> 50:42.000 align:start position:10% line:84.66% size:75% more blue in color bounces off 50:42.000 --> 50:43.533 align:start position:10% line:84.66% size:75% of particles in the atmosphere 50:43.533 --> 50:44.833 align:start position:10% line:84.66% size:70% before coming to the ground. 50:44.833 --> 50:46.366 align:start position:10% line:84.66% size:67.5% When you look at the sky on 50:46.366 --> 50:48.400 align:start position:10% line:84.66% size:80% Earth, you see the light that is 50:48.400 --> 50:49.900 align:start position:10% line:84.66% size:62.5% more blue in color having 50:49.900 --> 50:51.533 align:start position:10% line:84.66% size:75% scattered off of the particles 50:51.533 --> 50:52.933 align:start position:10% line:84.66% size:75% in the sky, then coming to the 50:52.933 --> 50:54.766 align:start position:10% line:84.66% size:65% ground which you then see. 50:54.766 --> 50:55.866 align:start position:10% line:84.66% size:77.5% We're going to demonstrate this 50:55.866 --> 50:57.066 align:start position:10% line:84.66% size:12.5% here. 50:57.066 --> 50:58.333 align:start position:10% line:84.66% size:72.5% We have a tank of water and a 50:58.333 --> 51:00.433 align:start position:10% line:84.66% size:67.5% lamp which is going to make 51:00.433 --> 51:02.100 align:start position:10% line:84.66% size:30% white light. 51:02.100 --> 51:03.366 align:start position:10% line:84.66% size:80% See the white light is projected 51:03.366 --> 51:04.933 align:start position:10% line:84.66% size:62.5% right here on the screen. 51:04.933 --> 51:06.533 align:start position:10% line:84.66% size:72.5% What we're going to do is now 51:06.533 --> 51:07.700 align:start position:10% line:84.66% size:75% mix some milk into the tank of 51:07.700 --> 51:09.966 align:start position:10% line:84.66% size:15% water. 51:09.966 --> 51:11.333 align:start position:10% line:84.66% size:77.5% The particles of milk are going 51:11.333 --> 51:14.733 align:start position:10% line:84.66% size:80% to scatter, or some of the light 51:14.733 --> 51:16.733 align:start position:10% line:84.66% size:72.5% is going to bounce off of it. 51:16.733 --> 51:18.266 align:start position:10% line:84.66% size:80% We'll see in just a moment here. 51:18.266 --> 51:20.333 align:start position:10% line:84.66% size:60% Some of the light passes 51:20.333 --> 51:23.266 align:start position:10% line:84.66% size:42.5% straight through. 51:23.266 --> 51:24.933 align:start position:10% line:84.66% size:70% That light is more yellow in 51:24.933 --> 51:27.066 align:start position:10% line:84.66% size:65% color, we see there on the 51:27.066 --> 51:28.366 align:start position:10% line:84.66% size:17.5% screen. 51:28.366 --> 51:29.466 align:start position:10% line:84.66% size:75% Whereas the light that is more 51:29.466 --> 51:30.900 align:start position:10% line:84.66% size:80% blue in color comes straight out 51:30.900 --> 51:32.200 align:start position:10% line:84.66% size:75% of the front of the tank after 51:32.200 --> 51:33.433 align:start position:10% line:84.66% size:80% having bounced off of, or having 51:33.433 --> 51:34.733 align:start position:10% line:84.66% size:77.5% scattered off of, the particles 51:34.733 --> 51:36.066 align:start position:10% line:84.66% size:20% of milk. 51:36.066 --> 51:37.533 align:start position:10% line:84.66% size:75% This is a demonstration of why 51:37.533 --> 51:39.266 align:start position:10% line:84.66% size:40% the sky is blue. 51:39.266 --> 51:40.933 align:start position:10% line:84.66% size:25% [applause] 51:45.400 --> 51:46.933 align:start position:10% line:84.66% size:80% >> So when you look at the sun-- 51:46.933 --> 51:48.166 align:start position:10% line:84.66% size:72.5% >> Never look directly at the 51:48.166 --> 51:49.333 align:start position:10% line:84.66% size:25% sun, kids. 51:49.333 --> 51:50.566 align:start position:10% line:84.66% size:70% It's very bad for your eyes, 51:50.566 --> 51:52.033 align:start position:10% line:84.66% size:70% very dangerous, don't do it. 51:52.033 --> 51:53.666 align:start position:10% line:84.66% size:47.5% >> Very good point. 51:53.666 --> 51:54.966 align:start position:10% line:84.66% size:80% Perhaps if you look at a picture 51:54.966 --> 51:56.166 align:start position:10% line:84.66% size:80% of the sun, you will see that it 51:56.166 --> 51:57.366 align:start position:10% line:84.66% size:65% is yellow, and the sky all 51:57.366 --> 51:58.700 align:start position:10% line:84.66% size:45% around it is blue. 51:58.700 --> 52:00.300 align:start position:10% line:84.66% size:77.5% Of course, this isn't true here 52:00.300 --> 52:01.500 align:start position:10% line:84.66% size:20% on Mars. 52:01.500 --> 52:03.000 align:start position:10% line:84.66% size:57.5% This is only for Earth. 52:03.000 --> 52:04.266 align:start position:10% line:84.66% size:80% Here on Mars our sky is actually 52:04.266 --> 52:05.566 align:start position:10% line:84.66% size:62.5% more of a yellow, kind of 52:05.566 --> 52:07.233 align:start position:10% line:84.66% size:47.5% butterscotch color. 52:07.233 --> 52:09.533 align:start position:10% line:84.66% size:77.5% The reason for this is that our 52:09.533 --> 52:10.900 align:start position:10% line:84.66% size:70% Mars atmosphere is different 52:10.900 --> 52:12.500 align:start position:10% line:84.66% size:50% than it is on Earth. 52:12.500 --> 52:14.400 align:start position:10% line:84.66% size:77.5% The atmosphere is much thinner, 52:14.400 --> 52:15.566 align:start position:10% line:84.66% size:67.5% and we have a lot more dust 52:15.566 --> 52:16.933 align:start position:10% line:84.66% size:25% particles. 52:16.933 --> 52:20.233 align:start position:10% line:84.66% size:72.5% So we have a more yellow sky. 52:20.233 --> 52:21.300 align:start position:10% line:84.66% size:75% >> Now I have a very important 52:21.300 --> 52:22.500 align:start position:10% line:84.66% size:60% question for all of you. 52:22.500 --> 52:25.266 align:start position:10% line:84.66% size:65% Who likes to pop balloons? 52:25.266 --> 52:26.400 align:start position:10% line:84.66% size:22.5% Oh, good! 52:26.400 --> 52:28.600 align:start position:10% line:84.66% size:35% I was worried. 52:28.600 --> 52:31.933 align:start position:10% line:84.66% size:72.5% We're going to pop a balloon. 52:31.933 --> 52:33.566 align:start position:10% line:84.66% size:72.5% But we're not going to pop it 52:33.566 --> 52:35.400 align:start position:10% line:84.66% size:75% with a pin, or by crushing it, 52:35.400 --> 52:36.566 align:start position:10% line:84.66% size:40% or squeezing it. 52:36.566 --> 52:37.766 align:start position:10% line:84.66% size:80% We are going to pop it using the 52:37.766 --> 52:40.100 align:start position:10% line:84.66% size:37.5% power of light. 52:40.100 --> 52:41.233 align:start position:10% line:84.66% size:72.5% We have a laser here that I'm 52:41.233 --> 52:42.833 align:start position:10% line:84.66% size:42.5% going to turn on. 52:42.833 --> 52:45.033 align:start position:10% line:84.66% size:55% You can see the laser. 52:45.033 --> 52:46.900 align:start position:10% line:84.66% size:55% Bring down the lights. 52:53.266 --> 52:54.700 align:start position:10% line:84.66% size:72.5% Now what we're going to do is 52:54.700 --> 52:58.600 align:start position:10% line:84.66% size:75% put this balloon in a box, and 52:58.600 --> 52:59.933 align:start position:10% line:84.66% size:67.5% then shine the laser at it. 52:59.933 --> 53:02.300 align:start position:10% line:84.66% size:55% Then see what happens. 53:02.300 --> 53:03.966 align:start position:10% line:84.66% size:27.5% Here we go. 53:03.966 --> 53:06.800 align:start position:10% line:84.66% size:40% Three, two, one! 53:06.800 --> 53:09.000 align:start position:10% line:84.66% size:12.5% [pop] 53:09.000 --> 53:11.066 align:start position:10% line:84.66% size:25% [applause] 53:14.733 --> 53:16.433 align:start position:10% line:84.66% size:35% What happened? 53:16.433 --> 53:17.933 align:start position:10% line:84.66% size:75% The balloon absorbed the light 53:17.933 --> 53:19.433 align:start position:10% line:84.66% size:65% from the laser causing the 53:19.433 --> 53:20.600 align:start position:10% line:84.66% size:47.5% balloon to heat up. 53:20.600 --> 53:21.833 align:start position:10% line:84.66% size:60% This caused it to burst. 53:21.833 --> 53:22.966 align:start position:10% line:84.66% size:80% Would everybody like to see that 53:22.966 --> 53:24.300 align:start position:10% line:84.66% size:15% again? 53:24.300 --> 53:25.700 align:start position:10% line:84.66% size:20% >> Yeah! 53:25.700 --> 53:27.366 align:start position:10% line:84.66% size:32.5% >> Excellent. 53:27.366 --> 53:28.566 align:start position:10% line:84.66% size:77.5% We're going to do it again, but 53:28.566 --> 53:29.733 align:start position:10% line:84.66% size:65% we have something slightly 53:29.733 --> 53:30.933 align:start position:10% line:84.66% size:50% different this time. 53:30.933 --> 53:32.000 align:start position:10% line:84.66% size:77.5% >> What we have here is we have 53:32.000 --> 53:34.433 align:start position:10% line:84.66% size:75% a balloon inside of a balloon. 53:34.433 --> 53:35.866 align:start position:10% line:84.66% size:72.5% What do you think is going to 53:35.866 --> 53:37.400 align:start position:10% line:84.66% size:77.5% happen if we shoot the laser at 53:37.400 --> 53:39.100 align:start position:10% line:84.66% size:37.5% these balloons? 53:39.100 --> 53:41.400 align:start position:10% line:84.66% size:70% Will one blow up but not the 53:41.400 --> 53:42.533 align:start position:10% line:84.66% size:15% other? 53:42.533 --> 53:44.800 align:start position:10% line:84.66% size:47.5% Will they both pop? 53:44.800 --> 53:46.000 align:start position:10% line:84.66% size:47.5% Should we find out? 53:46.000 --> 53:47.566 align:start position:10% line:84.66% size:17.5% >> Yes! 53:47.566 --> 53:48.866 align:start position:10% line:84.66% size:67.5% >> Yes, we should find out. 53:48.866 --> 53:51.300 align:start position:10% line:84.66% size:65% >> Let's see what happens. 53:51.300 --> 53:52.500 align:start position:10% line:84.66% size:22.5% In we go. 53:52.500 --> 53:54.100 align:start position:10% line:84.66% size:50% >> Okay, here we go! 53:54.100 --> 53:57.333 align:start position:10% line:84.66% size:40% Three, two, one! 53:57.333 --> 53:59.333 align:start position:10% line:84.66% size:12.5% [pop] 53:59.333 --> 54:01.400 align:start position:10% line:84.66% size:25% [applause] 54:03.866 --> 54:05.933 align:start position:10% line:84.66% size:55% >> What happened here? 54:05.933 --> 54:08.633 align:start position:10% line:84.66% size:80% The inner balloon has popped and 54:08.633 --> 54:10.866 align:start position:10% line:84.66% size:75% the outer balloon is still all 54:10.866 --> 54:12.300 align:start position:10% line:84.66% size:22.5% inflated. 54:12.300 --> 54:13.666 align:start position:10% line:84.66% size:30% Why is this? 54:13.666 --> 54:14.933 align:start position:10% line:84.66% size:70% The outer balloon is a clear 54:14.933 --> 54:16.266 align:start position:10% line:84.66% size:15% color. 54:16.266 --> 54:17.766 align:start position:10% line:84.66% size:62.5% The inner one was purple. 54:17.766 --> 54:18.966 align:start position:10% line:84.66% size:70% The laser just went straight 54:18.966 --> 54:21.100 align:start position:10% line:84.66% size:80% through the transparent balloon, 54:21.100 --> 54:22.200 align:start position:10% line:84.66% size:60% and heated up the purple 54:22.200 --> 54:23.300 align:start position:10% line:84.66% size:20% balloon. 54:23.300 --> 54:24.500 align:start position:10% line:84.66% size:25% It popped. 54:24.500 --> 54:26.233 align:start position:10% line:84.66% size:65% But the clear one did not. 54:26.233 --> 54:29.100 align:start position:10% line:84.66% size:25% [applause] 54:33.033 --> 54:35.233 align:start position:10% line:84.66% size:77.5% >> Well, we have been delighted 54:35.233 --> 54:38.800 align:start position:10% line:84.66% size:80% to share our knowledge with you. 54:38.800 --> 54:39.866 align:start position:10% line:84.66% size:72.5% >> Unfortunately, that is all 54:39.866 --> 54:41.133 align:start position:10% line:84.66% size:42.5% the time we have. 54:41.133 --> 54:42.500 align:start position:10% line:84.66% size:37.5% We must go now. 54:42.500 --> 54:43.933 align:start position:10% line:84.66% size:67.5% >> together: Light Brigade, 54:43.933 --> 54:45.333 align:start position:10% line:84.66% size:17.5% charge! 54:45.333 --> 54:47.066 align:start position:10% line:84.66% size:25% [applause] 54:49.700 --> 54:50.766 align:start position:10% line:84.66% size:70% >> Well, Professor Sprott, I 54:50.766 --> 54:52.100 align:start position:10% line:84.66% size:80% want to thank you for coming and 54:52.100 --> 54:53.766 align:start position:10% line:84.66% size:70% visiting us here on Mars and 54:53.766 --> 54:55.066 align:start position:10% line:84.66% size:57.5% showing us some of your 54:55.066 --> 54:56.866 align:start position:10% line:84.66% size:37.5% demonstrations. 54:56.866 --> 54:58.700 align:start position:10% line:84.66% size:65% I think all of us Martians 54:58.700 --> 55:00.766 align:start position:10% line:84.66% size:75% should give Professor Sprott a 55:00.766 --> 55:03.166 align:start position:10% line:84.66% size:80% very loud applause for giving us 55:03.166 --> 55:06.466 align:start position:10% line:84.66% size:77.5% 30 years of Wonders of Physics. 55:06.466 --> 55:08.600 align:start position:10% line:84.66% size:52.5% [cheers and applause] 55:14.600 --> 55:15.766 align:start position:10% line:84.66% size:75% Thank you very much, Professor 55:15.766 --> 55:17.400 align:start position:10% line:84.66% size:17.5% Sprott. 55:17.400 --> 55:18.666 align:start position:10% line:84.66% size:77.5% Now another thing that I'm very 55:18.666 --> 55:20.066 align:start position:10% line:84.66% size:75% fond of looking at pictures of 55:20.066 --> 55:22.500 align:start position:10% line:84.66% size:77.5% are clouds, and maybe you could 55:22.500 --> 55:24.900 align:start position:10% line:84.66% size:77.5% show us something about clouds. 55:24.900 --> 55:26.166 align:start position:10% line:84.66% size:72.5% >> Well, we do have beautiful 55:26.166 --> 55:27.433 align:start position:10% line:84.66% size:50% clouds on the Earth. 55:27.433 --> 55:28.700 align:start position:10% line:84.66% size:80% You may not know what those are, 55:28.700 --> 55:29.833 align:start position:10% line:84.66% size:75% but they're white puffy things 55:29.833 --> 55:31.566 align:start position:10% line:84.66% size:75% that are up in the atmosphere. 55:31.566 --> 55:35.066 align:start position:10% line:84.66% size:70% In all of our shows, for 256 55:35.066 --> 55:37.200 align:start position:10% line:84.66% size:67.5% presentations, we've always 55:37.200 --> 55:39.433 align:start position:10% line:84.66% size:75% concluded by making a cloud to 55:39.433 --> 55:41.233 align:start position:10% line:84.66% size:55% show you how it works. 55:41.233 --> 55:43.600 align:start position:10% line:84.66% size:77.5% In order to do that I have back 55:43.600 --> 55:45.566 align:start position:10% line:84.66% size:77.5% here a tank of liquid nitrogen, 55:45.566 --> 55:48.033 align:start position:10% line:84.66% size:75% the same stuff we used before. 55:48.033 --> 55:49.833 align:start position:10% line:84.66% size:80% But it's a very large container, 55:49.833 --> 55:53.033 align:start position:10% line:84.66% size:75% it's 25 liters of this liquid. 55:53.033 --> 55:54.833 align:start position:10% line:84.66% size:80% What we do is force the nitrogen 55:54.833 --> 55:56.300 align:start position:10% line:84.66% size:75% gas into here, that forces the 55:56.300 --> 55:58.233 align:start position:10% line:84.66% size:77.5% liquid up into this pipe on the 55:58.233 --> 55:59.866 align:start position:10% line:84.66% size:70% top, which has about a dozen 55:59.866 --> 56:01.366 align:start position:10% line:84.66% size:42.5% holes on the top. 56:01.366 --> 56:02.766 align:start position:10% line:84.66% size:72.5% It comes out and it cools the 56:02.766 --> 56:04.233 align:start position:10% line:84.66% size:10% air. 56:04.233 --> 56:05.533 align:start position:10% line:84.66% size:67.5% When that happens the water 56:05.533 --> 56:07.366 align:start position:10% line:84.66% size:77.5% vapor in the air condenses into 56:07.366 --> 56:10.300 align:start position:10% line:84.66% size:75% tiny droplets of liquid water. 56:10.300 --> 56:12.600 align:start position:10% line:84.66% size:70% That's what we call a cloud. 56:12.600 --> 56:15.633 align:start position:10% line:84.66% size:77.5% With that, I'll take my helmet. 56:15.633 --> 56:17.100 align:start position:10% line:84.66% size:80% I want to invite you all to come 56:17.100 --> 56:19.200 align:start position:10% line:84.66% size:75% to the Earth next year for our 56:19.200 --> 56:20.800 align:start position:10% line:84.66% size:72.5% 31st season of The Wonders of 56:20.800 --> 56:22.500 align:start position:10% line:84.66% size:20% Physics. 56:22.500 --> 56:24.200 align:start position:10% line:84.66% size:65% For now, thank you all for 56:24.200 --> 56:26.333 align:start position:10% line:84.66% size:17.5% coming. 56:26.333 --> 56:28.866 align:start position:10% line:84.66% size:25% [applause] 56:28.866 --> 56:31.633 align:start position:10% line:84.66% size:7.5% ♪ ♪ 56:46.833 --> 56:48.833 align:start position:10% line:84.66% size:25% [applause] 56:48.833 --> 56:51.300 align:start position:10% line:84.66% size:7.5% ♪ ♪