A coil with magnetic moment `1.45 A -m^2` is oriented initially with its magnetic moment antiparallel to a uniform `0.835 T` magnetic field. What is the change in potential energy of the coil when it is rotated `180^@` so that its magnetic moment is parallel to the field?

Explanation

To solve the problem, we need to calculate the change in potential energy of the coil when it is rotated from an orientation where its magnetic moment is antiparallel to the magnetic field to an orientation where it is parallel to the magnetic field.

### Step-by-Step Solution:

1. **Identify the Given Values:**
- Magnetic moment, \( m = 1.45 \, \text{A} \cdot \text{m}^2 \)
- Magnetic field strength, \( B = 0.835 \, \text{T} \)

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