What is the function of the radial magnetic field in the moving coil galvanometer?

Explanation

### Step-by-Step Solution:

1. **Definition of Radial Magnetic Field**: The radial magnetic field in a moving coil galvanometer is a magnetic field that is directed radially outward from the center of the coil. This means that the magnetic field lines are straight and uniformly distributed around the coil.

2. **Uniformity of the Magnetic Field**: The radial magnetic field is designed to be uniform, meaning that its strength and direction do not vary across the area where the coil moves. This uniformity is crucial for the proper functioning of the galvanometer.

3. **Torque on the Coil**: When a current passes through the coil placed in the radial magnetic field, it experiences a torque (τ) due to the interaction between the magnetic field and the current in the coil. The torque is given by the formula:
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