A solid disk with a radius of 12 m and mass of 5 kg is rotating on a frictionless surface. If 450 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
Dec 3, 2017

The torque is =8.95Nm

Explanation:

Apply the equation

P=tau omega

The power is P=450W

The frequency is f=8Hz

The angular velocity is

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

Therefore,

The torque is

tau=P/omega=450/(16pi)=8.95Nm