Through a cartoon movie, Beakman explains why your stomach feels weird on a roller coaster and why the biggest hill is the first one. He hangs a bowling ball from the ceiling with a cable and then swings the ball to squish a watermelon (energy in and energy out). He then puts himself where the watermelon was and shows that the ball can't swing any farther than the point at which he lets go. Beakman goes on to explain that centripetal force prevents us from falling out of the roller coaster and demonstrates it. He uses a tray containing a glass of milk and a cupcake and quickly spins it around to show that nothing falls off. He then explains why inertia keeps us from falling to the ground and brings all of the concepts together.