A solid disk with a radius of 6 m and mass of 2 kg is rotating on a frictionless surface. If 3 W of power is used to increase the disk's rate of rotation, what torque is applied when the disk is rotating at 4 Hz?

1 Answer
Nov 16, 2017

The torque is =0.12Nm

Explanation:

Apply the equation

P=tau omega

The power is P=3W

The frequency is f=4Hz

The angular velocity is

omega=2pif=2xxpixx4=(8pi)rads^-1

Therefore,

The torque is

tau=P/omega=3/(8pi)=0.12Nm