Two particles A and B having charges q and 2q respectively are placed on a smooth table with a separation d. A third particle C is to be clamped on the table in such a way that the particles A and B remain at rest on the table under electrical forces. What should be the charge on C and where should it clamped?

Explanation

To solve the problem, we need to determine the charge on particle C and its position such that particles A and B remain at rest under the influence of electric forces.

### Step-by-Step Solution:

1. **Understanding the Configuration**:
- We have two charges: Charge A (q) and Charge B (2q) separated by a distance d.
- We need to place Charge C (let's denote it as Q) in such a way that A and B are in equilibrium.

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