# What torque would have to be applied to a rod with a length of #4 m# and a mass of #3 kg# to change its horizontal spin by a frequency of #3 Hz# over #2 s#?

##### 1 Answer

Nov 18, 2016

The torque applied to the rod is 37.68 Newton-metre.

#### Explanation:

Torque is defined as the product of moment of inertia and angular acceleration

Moment of inertia of rod is

angular velocity

Now the torque becomes

Substituting the given values we get,