A circular loop of radius 4.0 cm is placed in a horizontal plane and carries an electric current of 5.0 A in the clockwise direction as seen from above. Find the magnetic field (a) at a point 3.0 cm above the centre of the loop (b) at a point 3.0 cm below the centre of the loop.

Explanation

To solve the problem, we need to find the magnetic field at two points: one above the center of the loop and one below it. We will use the formula for the magnetic field along the axis of a circular current-carrying loop.

### Given Data:
- Radius of the loop, \( R = 4.0 \, \text{cm} = 4 \times 10^{-2} \, \text{m} \)
- Current, \( I = 5.0 \, \text{A} \)
- Distance above the center, \( X_1 = 3.0 \, \text{cm} = 3 \times 10^{-2} \, \text{m} \)
- Distance below the center, \( X_2 = 3.0 \, \text{cm} = 3 \times 10^{-2} \, \text{m} \)

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