A solid disk with a radius of 6 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 32 Hz?

1 Answer
Oct 13, 2017

The torque is =4.78Nm

Explanation:

The mass of the disc is m=9kg

The radius of the disc is r=6m

The power =P and the torque =tau are related by the following equation

P=tau omega

where omega= the angular velocity

Here,

The power is P=960W

The frequency is f=32Hz

The angular velocity is omega=2pif=2*pi*32=(64pi)rads^-1

Therefore,

the torque is tau=P/omega=960/(64pi)=4.78Nm