A sperical shell of radius R with uniform charge q is expanded to a radius 2R. Find the work perfomed by the electric forces and external agent against electric forces in this process.

Explanation

To solve the problem of finding the work performed by the electric forces and the external agent when a spherical shell of radius R with uniform charge q is expanded to a radius of 2R, we can follow these steps:

### Step 1: Understand the Initial and Final States
- We have a spherical shell with a uniform charge \( q \) at an initial radius \( R \).
- The shell is expanded to a final radius of \( 2R \).

### Step 2: Calculate the Initial Potential Energy \( U_{\text{initial}} \)
- The potential energy \( U \) of a uniformly charged spherical shell is given by the formula:
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