A solid disk with a radius of 8 m and mass of 9 kg is rotating on a frictionless surface. If 960 W of power is used to increase the disk's rate of rotation, what torque is applied when the disk is rotating at 28 Hz?

1 Answer
Jan 3, 2018

The torque is =5.46Nm

Explanation:

Apply the equation

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

The power is P=960W

The frequency is f=28Hz

The angular velocity is

omega=2pif=2xxpixx28=(56pi)rads^-1

Therefore,

The torque is

tau=P/omega=960/(56pi)=5.46Nm