[填空题]
A teenager pushes tangential/ih 4n, ,ht rt:hs5udbly on a smallz 6iv(p l:xc8p hand-driven merry-go-round and is able to accelerate it from v c x68pl:ipz(rest to a frequency of 15 rpm in 10.0 s. Assume the merry-go-round is a uniform disk of radius 2.5 m and has a mass of 760 kg, and two children (each with a mass of 25 kg) sit opposite each other on the edge. Calculate the torque required to produce the acceleration, neglecting frictional torque. $\approx$ $m \cdot N$ What force is required at the edge? N