Repeat the previous problem if the particle C s displaced through a distance x along the line AB.

Explanation

To solve the problem step by step, we will analyze the forces acting on the particle C when it is displaced by a distance \( x \) along the line AB and derive the expression for the time period of its oscillatory motion.

### Step 1: Understand the Setup
We have two fixed charges, A and B, each with charge \( Q \), separated by a distance \( D \). A third charge, C, also with charge \( Q \), is initially placed at the midpoint of AB. When C is displaced by a distance \( x \) along the line AB, we need to analyze the forces acting on it.

**Hint:** Visualize the arrangement of the charges and the displacement of charge C.

### Step 2: Determine the New Positions
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