Two negative charges of a unit magnitude and a positive charge q are placed along a straight line. At what position and value of q will the system be in equilibrium? (Negative charges are fixed).

Explanation

To solve the problem of finding the position and value of the charge \( q \) such that the system is in equilibrium, we will follow these steps:

### Step 1: Define the Charges and Their Positions
We have two fixed negative charges, \( Q_1 = -1 \, C \) and \( Q_2 = -1 \, C \), placed at positions \( x = 0 \) and \( x = 2L \) respectively. We need to find the position \( x \) and the value of a positive charge \( q \) that will be placed between these two charges.

### Step 2: Determine the Position of Charge \( q \)
To achieve equilibrium, the charge \( q \) must be placed at the midpoint between the two negative charges. Thus, the position of \( q \) will be at \( x = L \).

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