A charge `q` is uniformly distributed on a non-conducting disc of radius `R`. It is rotated with an angular speed co about an axis passing through the centre of mass of the disc and perpendicular to its plane. Find the magnetic moment of the disc.

Explanation

To find the magnetic moment of a uniformly charged non-conducting disc that is rotating about an axis through its center and perpendicular to its plane, we can follow these steps:

### Step 1: Understand the given parameters
We have:
- Charge \( q \) uniformly distributed over a disc of radius \( R \).
- The disc is rotating with an angular speed \( \omega \).

### Step 2: Recall the relationship between magnetic moment and angular momentum
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