A solid disk with a radius of 5 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
Feb 28, 2017

The torque is =0.12Nm

Explanation:

The power and the torque are related by the following equation

P=tau omega

Power =3W

The angular velocity =4*2pi=8pirads^-1

The torque is

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