A solid disk with a radius of 2 m and mass of 3 kg is rotating on a frictionless surface. If 36 W of power is used to increase the disk's rate of rotation, what torque is applied when the disk is rotating at 8 Hz?

1 Answer
Nov 21, 2017

The torque is =0.72Nm

Explanation:

Apply the equation

P=tau omega

The power is P=36W

The frequency is f=8Hz

The angular velocity is

omega=2pif=2xxpixx8=(16pi)rads^-1

Therefore,

The torque is

tau=P/omega=36/(16pi)=0.72Nm