A pendulum bob of mass 80mg and carrying a charge of `2xx 10^(-8)C` is at rest in a uniform, horizontal electric field of 20k `Vm^-1.` Find the tension in the thread.

Explanation

To find the tension in the thread of a pendulum bob that is affected by an electric field, we will follow these steps:

### Step 1: Identify the Given Values
- Mass of the pendulum bob, \( m = 80 \, \text{mg} = 80 \times 10^{-3} \, \text{g} = 80 \times 10^{-6} \, \text{kg} = 0.08 \, \text{g} \)
- Charge on the bob, \( Q = 2 \times 10^{-8} \, \text{C} \)
- Electric field strength, \( E = 20 \, \text{kV/m} = 20,000 \, \text{V/m} \)
- Acceleration due to gravity, \( g = 10 \, \text{m/s}^2 \)

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