Two charges `-q and + q ` are located at points ` A (0, 0, -a ) and B(0, 0 + a ) `. How much work is done in moving a test charge from point ` (b, 0, 0 ) ` to ` Q (-b, 0, 0) ` ?

Explanation

To solve the problem of calculating the work done in moving a test charge from point \( (b, 0, 0) \) to \( (-b, 0, 0) \) in the presence of two charges \( -q \) and \( +q \) located at points \( A(0, 0, -a) \) and \( B(0, 0, a) \) respectively, we can follow these steps:

### Step 1: Understand the Configuration
We have two charges:
- Charge \( -q \) at point \( A(0, 0, -a) \)
- Charge \( +q \) at point \( B(0, 0, a) \)

The test charge \( Q \) is being moved from point \( P(b, 0, 0) \) to point \( S(-b, 0, 0) \).
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