Two charges of `5muC` and `20muC` are placed 20 cm apart. Calculate the work done in bringing the charges closer to 15 cm apart.

Explanation

To solve the problem of calculating the work done in bringing two charges closer together, we will follow these steps:

### Step 1: Understand the Problem
We have two charges, \( q_1 = 5 \, \mu C = 5 \times 10^{-6} \, C \) and \( q_2 = 20 \, \mu C = 20 \times 10^{-6} \, C \), initially placed 20 cm apart. We want to find the work done when they are brought closer to 15 cm apart.

### Step 2: Convert Distances to Meters
Convert the distances from centimeters to meters:
- Initial distance \( r_1 = 20 \, cm = 20 \times 10^{-2} \, m = 0.2 \, m \)
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