The self-inductances of two identical coils are 0.1H. They are wound over each other. Mutual inductance will be-

Options

A. 0.1H
B. 0.2H
C. 0.01H
D. 0.05H

Explanation

To solve the problem of finding the mutual inductance of two identical coils with a self-inductance of 0.1 H, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Given Information**:
- We have two identical coils, each with a self-inductance \( L = 0.1 \, \text{H} \).

2. **Identify the Formula for Mutual Inductance**:
- The mutual inductance \( M \) between two coils can be calculated using the formula:
\[ M = \sqrt{L_1 \cdot L_2} \]
- Since the coils are identical, we have \( L_1 = L_2 = L \).

3. **Substitute the Values into the Formula**:
- Substituting the values into the formula:
\[ M = \sqrt{0.1 \, \text{H} \cdot 0.1 \, \text{H}} \]

4. **Calculate the Mutual Inductance**:
- Performing the calculation:
\[ M = \sqrt{0.01 \, \text{H}^2} = 0.1 \, \text{H} \]

5. **Conclusion**:
- Therefore, the mutual inductance \( M \) of the two coils is \( 0.1 \, \text{H} \).

### Final Answer:
The mutual inductance of the two identical coils is \( 0.1 \, \text{H} \).

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