Question

A playground merry-go-round has a radius of 1.5 m and mass of 200 kg, and turns with negligible friction about a vertical axle through its center. A child applies a constant force that produces a torque of 50 N·m to the merry-go-round. Its moment of inertia is given by I = ½MR2. The next four questions have to do with this rotating merry-go-round. Determine the angular acceleration of the merry-go-round in rad/s2. a. 0.047 rad/s2 b. 0.222 rad/s2 c. 0.965 rad/s2 d. 3.1 rad/s2

If the merry-go-round makes 3 revolutions, how much rotational work was done by the child? a. 942.5 J b. 1891 J c. 3567 J d. 4213 J

If it took 13 s for the merry-go-round to complete 3 revolutions, what was the power generated by the child? a. 15.2 W b. 37.6 W c. 60 W d. 72.5 W

If the merry-go-round starts from rest, what is its kinetic energy after the 3 revolutions? Hint: use the work-energy theorem. a. 201.2 J b. 942.5 J c. 789.3 J d. 12.9 J

Answer 1

Answer