4. Remember the lab to test this Achieve result? When you rolled cylinders and balls down a ramp, the Gravitational Potential Energy Difference AU- (r rarity = mgAh Mechanical Energy EJh'L'han'uf E K + U H C AE'II'IJIJINHI n _ M+ AL [H mm :0 [I I3 ' \\ full -* results fell short ofthe prediction. That calculation was actually for a ball sliding without friction. [They show a ball on the ramp, and nearly every student who watches interprets the situation as the ball rolling, but it's supposed to be sliding without rolling.) For a sliding ball the kinetic energy is 7\"\" For a rolling wheel, or hollow cylinder, it' s what you found In Q4 on HW ii. A. Find an expression for the speed a simple wheel/hollow cylinder should be rolling when it gets to the bottom ofa ramp B. A ball has a smaller moment of inertia, because the mass on average is closer to the axis of rotation, like you with your hands close to your chest. Would that mean it would move faster or slower than a hollow cylinder? C. Go back to your data from labr that I asked you to save: Do they now match the theoretical predictions, for the speed of a cylinder, for whether a ball rolls faster or slower? (There are a few people who weren't in lab for various reasons...lf you have good data to share, it would be great to post it for others on Piazza.)