Lester and Phoebe have a contest to see who can rotate an apparatus the fastest. The two apparatuses weigh exactly the same, but Phoebe wins because the weights on hers are closer to the middle. This demonstration explains how figure skaters can spin faster when they pull their arms and legs inward.
Galileo explains to his student that, if two balls are dropped at the same height, they will both hit the ground at the same time, regardless of their weight.
Mr. Seaver begins teaching the class a lesson on gravity out of the textbook. He is especially confused by the book's claim that a coin and a feather will fall at exactly the same speed. After Luke challenges him to prove it, he tests the claim.