A solid disk with a radius of 2 m and mass of 3 kg is rotating on a frictionless surface. If 18 W of power is used to increase the disk's rate of rotation, what torque is applied when the disk is rotating at 6 Hz?

1 Answer
Jan 16, 2018

The torque is =0.48Nm

Explanation:

Apply the equation

"Power (W)" ="torque(Nm)"xx"angular velocity" (rad s^-1)

The power is P=18W

The frequency is f=6Hz

The angular velocity is

omega=2pif=2xxpixx6=(12pi)rads^-1

Therefore,

The torque is

tau=P/omega=18/(12pi)=0.48Nm