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 step by step, we need to find the charge on particle C and its position such that particles A and B remain at rest under the influence of electrical forces.

### Step 1: Understanding the Problem
We have two charges:
- Charge A = \( q \)
- Charge B = \( 2q \)

They are separated by a distance \( d \). We need to find the charge \( C \) and its position such that the net force on both A and B is zero.
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