Two electrons are fixed 4.0 cm apart. Another electron is shot from infinity and stops midway between the two. What is its initial speed?

Explanation

To solve the problem, we will use the principle of conservation of energy. The initial kinetic energy of the electron when it is shot from infinity will be converted into potential energy when it stops midway between the two fixed electrons.

### Step-by-Step Solution:

1. **Identify the Given Data:**
- Distance between the two fixed electrons, \( d = 4.0 \, \text{cm} = 0.04 \, \text{m} \).
- The distance from each fixed electron to the point where the moving electron stops is \( \frac{d}{2} = 2.0 \, \text{cm} = 0.02 \, \text{m} \).
- Charge of an electron, \( q = 1.6 \times 10^{-19} \, \text{C} \).
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