A circular disc of 49 kg and radius 50 cm is rotating at a speed of 120 rotations per minute. Calculate its kinetic energy if is moment of inertia about the axis of rotation is `1/2 mr^(2)`.

Explanation

To calculate the kinetic energy of a rotating circular disc, we can follow these steps:

### Step 1: Identify the given values
- Mass of the disc (m) = 49 kg
- Radius of the disc (r) = 50 cm = 0.5 m (convert cm to m)
- Rotational speed (N) = 120 revolutions per minute (rpm)

### Step 2: Convert the rotational speed to radians per second
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