An object with a mass of 3 kg is traveling in a circular path of a radius of 7 m. If the object's angular velocity changes from 6 Hz to 7 Hz in 3 s, what torque was applied to the object?

1 Answer
Apr 25, 2017

The torque was =307.9Nm

Explanation:

The torque is the rate of change of angular momentum

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

The moment of inertia is =I

For the object, I=(mr^2)

So, I=(3*(7)^2)=147kgm^2

The rate of change of angular velocity is

(domega)/dt=(7-6)/3*2pi

=(2/3pi) rads^(-2)

So the torque is tau=147*(2/3pi) Nm=307.9Nm