A flywheel of mass `25 kg` has a radius of `0.2 m`. It is making 240 rpm. What is the torque necessary to bring it to rest in `20 s` ? If the torque is due to a force applies tangentially on the rim of the wheel, what is the magnitude of the force ? Assume that mass of flywheel is concentrated at its rim.

Explanation

To solve the problem step by step, we will follow these steps:

### Step 1: Convert Angular Velocity from RPM to Radians per Second
The initial angular velocity (ω_initial) is given as 240 revolutions per minute (rpm). We need to convert this to radians per second.

\[ \omega_{\text{initial}} = 240 \, \text{rpm} \times \frac{2\pi \, \text{radians}}{1 \, \text{revolution}} \times \frac{1 \, \text{minute}}{60 \, \text{seconds}} = 8\pi \, \text{radians/second} \]
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