An object with a mass of 8 kg is traveling in a circular path of a radius of 12 m. If the object's angular velocity changes from 15 Hz to 4 Hz in 5 s, what torque was applied to the object?

1 Answer
Sep 19, 2017

The torque was =15924.1Nm

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

The mass of the object is m=8kg

The radius is r=12m

For the object, I=mr^2

So, I=8*(12)^2=1152kgm^2

And the rate of change of angular velocity is

(d omega)/dt=(Deltaomega)/t=(30pi-8pi)/5=22/5pirads^-2

So,

The torque is

tau=1152*22/5pi=15924.1Nm