Two point charges Q are kept fixed on XY-plane at points A(0, d) and B(0, -d). Another point charge -q with mass m is held at a point, on the positive side of X-axis that is at the distance 2d from both the fixed point charges. What will be the magnitude of acceleration of the negative point charge (i) just after it is released from its location? (ii) at an instant it crosses the origin?

Explanation

To solve the problem step by step, we will analyze the forces acting on the negative charge -q at two different instances: just after it is released and when it crosses the origin.

### Step 1: Understanding the Setup
We have two fixed point charges, both equal to Q, located at points A(0, d) and B(0, -d) on the XY-plane. The negative charge -q is placed at point C(2d, 0) on the positive X-axis.

### Step 2: Calculate the Force on Charge -q Just After Release
1. **Identify the distances**:
- The distance from charge -q at point C to charge Q at point A is \( AC = 2d \).
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