A coil of `40 H` inductance is connected in series with a resistance of `8` ohm and the combination is joined to the terminals of a `2 V` battery. The time constant of the circuit

Options

A. `5s`
B. `1//5s`
C. `40s`
D. `20s`

Explanation

To find the time constant of the given RL circuit, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given values**:
- Inductance (L) = 40 H (Henry)
- Resistance (R) = 8 Ω (ohm)

2. **Recall the formula for the time constant (τ)**:
The time constant for an RL circuit is given by the formula:
\[ \tau = \frac{L}{R} \]

3. **Substitute the values into the formula**:
Substitute the values of L and R into the time constant formula:
\[ \tau = \frac{40 \, \text{H}}{8 \, \Omega} \]

4. **Perform the calculation**:
Calculate the value:
\[ \tau = \frac{40}{8} = 5 \, \text{seconds} \]

5. **Conclusion**:
The time constant of the circuit is 5 seconds.

### Final Answer:
The time constant of the circuit is **5 seconds**.

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