On passing a current of 2A in a coil inductance 5H, the energy stored in it will be-

Options

A. 100 joule
B. 10 joule
C. 20 joule
D. 5 joule

Explanation

To find the energy stored in a coil with a given inductance and current, we can use the formula for the energy stored in an inductor:

\[ U = \frac{1}{2} L I^2 \]

where:
- \( U \) is the energy stored in joules,
- \( L \) is the inductance in henries,
- \( I \) is the current in amperes.

### Step-by-Step Solution:

1. **Identify the given values**:
- Inductance \( L = 5 \, \text{H} \)
- Current \( I = 2 \, \text{A} \)

2. **Substitute the values into the formula**:
\[ U = \frac{1}{2} \times L \times I^2 \]
\[ U = \frac{1}{2} \times 5 \times (2)^2 \]

3. **Calculate \( I^2 \)**:
\[ I^2 = 2^2 = 4 \]

4. **Substitute \( I^2 \) back into the equation**:
\[ U = \frac{1}{2} \times 5 \times 4 \]

5. **Perform the multiplication**:
\[ U = \frac{1}{2} \times 20 = 10 \, \text{J} \]

6. **Final result**:
The energy stored in the coil is \( 10 \, \text{J} \).

### Final Answer:
The energy stored in the coil is **10 joules**.