In a p-n junction having depletion layer of thickness `10^(-6)` m the potential across it is `0.3 V`. Then the electric field is
Hint = `E= V/d`

Options

A. `10^(-5) V/m`
B. `3xx 10^(5) V/m`
C. `10^(-6) V/m`
D. `3 xx 10^(7) V/m`

Answer

To find the electric field (E) across a p-n junction with a given depletion layer thickness (d) and potential (V), we can use the formula:

\[ E = \frac{V}{d} \]

### Step-by-Step Solution:

1. **Identify the given values**:
- Thickness of the depletion layer, \( d = 10^{-6} \) m
- Potential across the depletion layer, \( V = 0.3 \) V

2. **Substitute the values into the formula**:
\[ E = \frac{V}{d} = \frac{0.3 \, \text{V}}{10^{-6} \, \text{m}} \]

3. **Calculate the electric field**:
\[ E = \frac{0.3}{10^{-6}} = 0.3 \times 10^{6} \, \text{V/m} \]
\[ E = 3 \times 10^{5} \, \text{V/m} \]

4. **Final Result**:
The electric field across the depletion layer is \( E = 3 \times 10^{5} \, \text{V/m} \).

### Conclusion:
The correct option for the electric field is option 2: \( 3 \times 10^{5} \, \text{V/m} \).