An object with a mass of 2 kg is traveling in a circular path of a radius of 2 m. If the object's angular velocity changes from 1 Hz to 6 Hz in 1 s, what torque was applied to the object?

1 Answer
May 21, 2017

The torque was =251.3Nm

Explanation:

The torque is the rate of change of angular momentum

tau=(dL)/dt=(d(Iomega))/dt=I(domega)/dt

where I is the moment of inertia

For the object, I=mr^2

I=2*2^2=8kgm^2

The rate of change of angular velocity is

(domega)/dt=(6-1)/1*2pi

=(10pi) rads^(-2)

So the torque is tau=8*(10pi) Nm=80piNm=251.3Nm