A 23-kg boy stands 3 m from the center of a frictionless playground merry-go-round, which has a moment of inertia of 180 kg m2. The boy begins to run in a circular path with a speed of 0.6 m/s relative to the ground.

Question

A 23-kg boy stands 3 m from the center of a frictionless playground merry-go-round, which has a moment of inertia of 180 kg m2. The boy begins to run in a circular path with a speed of 0.6 m/s relative to the ground.
(a) Calculate the angular velocity of the merry-go-round in rad/s^2.
(b) Calculate the speed of the boy relative to the surface of the merry-go-round in m/s.

Damon · Accepted Answer

angular momentum of system remains zero I w = m v r 180 kg m^2 * w = 23 kg * .6 m/s * 3 m so w = .23 radians/second v merry = .23*3 = .69 m/s away from boy so .6 + .69 = 1.29 m/s

Maria · Answer

Thank you!