What is a radial magnetic field? How has it been achieved in moving coil galvanometer?

Explanation

### Step-by-Step Solution:

1. **Definition of Radial Magnetic Field**:
- A radial magnetic field is defined as a magnetic field in which the magnetic lines of force radiate outward from a central point. In this configuration, the direction of the magnetic field is always perpendicular to the plane of the coil at every point along the coil's path.

2. **Characteristics of Radial Magnetic Field**:
- In a radial magnetic field, the plane of the coil remains parallel to the magnetic field direction at all positions. This means that as the coil rotates, it experiences a uniform magnetic field, which is essential for accurate measurements in devices like galvanometers.

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