A particle a having a charge of `5.0 xx 10 ^(-7) C` is fixed in. a vertical wall. A second particle B of mass 100 g and. having equal charge is supended by a silk thread. of length 30 cm form the wall. The point of suspension is. 30 cm above the particle A. Find the angle of the thread. with the vertical when it stays in equilibrium.

Explanation

To solve the problem step by step, we will analyze the forces acting on particle B and apply Lamy's theorem to find the angle θ that the thread makes with the vertical.

### Step 1: Understand the Setup
We have two charged particles, A and B, both with a charge of \( Q = 5.0 \times 10^{-7} \, C \). Particle A is fixed on a vertical wall, and particle B is suspended by a silk thread of length \( L = 30 \, cm = 0.3 \, m \) from a point that is \( 30 \, cm \) above particle A.

### Step 2: Identify the Forces Acting on Particle B
1. **Weight (Mg)**: The weight of particle B acts downward and is given by \( Mg \), where \( M = 0.1 \, kg \) (mass of particle B) and \( g = 10 \, m/s^2 \).
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