WEBVTT 00:01.066 --> 00:07.333 position:10% line:85% size:80% (MUSIC) JOAN CARTAN-HANSEN, HOST: WHEN 00:07.333 --> 00:10.533 position:10% line:85% size:80% YOU USE THE SCIENTIFIC METHOD TO ANSWER A QUESTION, YOU START 00:10.533 --> 00:11.800 position:10% line:85% size:80% WITH AN EXPERIMENT. 00:11.800 --> 00:14.800 position:10% line:85% size:80% AND YOU DESIGN YOUR EXPERIMENT TO USE VARIABLES. 00:14.800 --> 00:17.166 position:10% line:85% size:80% THERE ARE THREE KINDS OF VARIABLES: INDEPENDENT, 00:17.166 --> 00:19.166 position:10% line:85% size:80% DEPENDENT AND CONTROLLED. 00:19.166 --> 00:21.800 position:10% line:85% size:80% LET'S SAY YOU WANT TO TEST IF A BIG DOG EATS MORE THAN A SMALL 00:21.800 --> 00:22.700 position:10% line:85% size:80% DOG. 00:22.700 --> 00:25.500 position:10% line:85% size:80% THE INDEPENDENT VARIABLE IS THE THING YOU CHANGE IN THE 00:25.500 --> 00:26.333 position:10% line:85% size:80% EXPERIMENT. 00:26.333 --> 00:29.066 position:10% line:85% size:80% IN THIS CASE, THE BIG DOG AND THE SMALL DOG. 00:29.066 --> 00:31.166 position:10% line:85% size:80% THE DEPENDENT VARIABLE IS ONE YOU MEASURE. 00:31.166 --> 00:34.600 position:10% line:85% size:80% IN OUR EXPERIMENT, IT'S THE AMOUNT OF FOOD EACH DOG EATS. 00:34.600 --> 00:37.367 position:10% line:85% size:80% THE CONTROLLED VARIABLES ARE THE THINGS YOU WANT TO REMAIN THE 00:37.367 --> 00:38.900 position:10% line:85% size:80% SAME OR CONSTANT. 00:38.900 --> 00:41.333 position:10% line:85% size:80% IN THIS EXPERIMENT, YOU WOULD WANT TO MAKE SURE THE DOGS EAT 00:41.333 --> 00:44.066 position:10% line:85% size:80% AT THE SAME TIME, EAT THE SAME FOOD, AND HAVE NOT 00:44.066 --> 00:47.066 position:10% line:85% size:80% EATEN FOR THE SAME AMOUNT OF TIME BEFORE THE EXPERIMENT. 00:47.066 --> 00:49.800 position:10% line:85% size:80% ONCE YOU'VE IDENTIFIED YOUR VARIABLES, YOU'RE READY FOR THE 00:49.800 --> 00:50.900 position:10% line:85% size:80% EXPERIMENT. 00:50.900 --> 00:53.333 position:10% line:85% size:80% AND YOUR DOGS ARE READY FOR DINNER. 00:53.333 --> 00:55.867 position:10% line:85% size:80% FOR MORE INFORMATION ABOUT INVENTIONS AND THE SCIENTIFIC 00:55.867 --> 00:58.000 position:10% line:85% size:80% METHOD, CHECK OUT THE SCIENCE TREK WEBSITE. 00:58.000 --> 01:01.066 position:10% line:85% size:80% YOU'LL FIND IT AT IDAHOPTV.ORG/SCIENCE TREK 01:01.066 --> 01:03.533 position:10% line:85% size:80% (MUSIC)