Question

1. You have been asked to design a new stunt for the opening of an ice show. A small skater glides down a ramp and along a short level stretch of ice. While gliding along the level stretch the skater, crouching low to the ground, then grabs a handle on the bottom end of a large vertical rod that is free to turn vertically about an axis through its center. The plan is for the skater to stay curled into as small a shape as possible while holding onto the 20 foot long rod to swing to the highest possible point. You have been asked to give the minimum height of the ramp necessary to accomplish this feat. The rod weighs 150 pounds and has a uniform mass distribution. Doing a quick integral tells you that the moment of inertia of this rod about its center is 1/12 of the product of its mass and length squared. The skater will weigh 110 pounds.

Answer 1

Hope this helps...I am not sure about American units...but the concept is totally correct