The figure shows scale drawings of four objects, each of the same mass and uniform thickness, with the mass distributed uniformly. Which one has the greatest moment of inertia when rotated at the same angular speed about an axis perpendicular to the plane of the drawing at point P?

A solid cylinder and a hollow pipe with equal masses and radii are released simultaneously at the top of a ramp and roll to the bottom without slipping, which one will reach the bottom first?

An ice skater spins without friction on the ice with her arms extended. When she folds in her arms,

Suppose you are designing an engineless car for a downhill coasting race (meaning that you want to maximize translational velocity). What type of wheels would be the best?