269471 A wheel at rest has M.I.2π2kgm2. It is rotated by a 60 W motor for one minute. The number of rotations made by the wheel in one minute is
p=τθt;θ=2πN
269472 The shaft of a motor is making1260rpm. The torque supplied by the motor is 100Nm. the power of motor is ( in KW)
p=πω
269473 An electric motor rotates a wheel at a constant angular velocity10rps while opposing torque is 10Nm. The power of that electric motor is
269474 The work done in increasing the angular frequency of a circular ring of mass2 kg and radius 25 cm from 10rpm to 20rpm about is axis
W=12I(ω22−ω12)