For the system in figure find Q for which resultant force on q is zero.

Explanation

To solve the problem of finding the value of \( Q \) for which the resultant force on the small charge \( q \) is zero, we can follow these steps:

### Step 1: Understand the Forces Acting on \( q \)
We have two small charges \( q \) and a charge \( Q \). The forces acting on \( q \) are:
- The repulsive force from the other small charge \( q \).
- The attractive force from the charge \( Q \).

Since both small charges \( q \) have the same sign, they will repel each other. Therefore, we need to find the value of \( Q \) such that the attractive force from \( Q \) balances the repulsive force from the other \( q \).
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