In a circuit, the current lags behind the voltage by a phase difference of `pi//2`, the circuit will contain which of the following ?

Options

A. (a)Only R
B. (b)Only L
C. (c)Only C
D. (d)R and C

Answer

To solve the question regarding the phase difference between current and voltage in a circuit, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Phase Difference**:
- In an AC circuit, the phase difference between current and voltage can indicate the presence of certain circuit elements. The phase difference is denoted in radians.

2. **Identify the Phase Relationships**:
- For a purely resistive circuit, the current and voltage are in phase (phase difference = 0).
- For a purely inductive circuit, the current lags behind the voltage by π/2 radians (90 degrees).
- For a purely capacitive circuit, the current leads the voltage by π/2 radians.

3. **Given Information**:
- The question states that the current lags behind the voltage by a phase difference of π/2.

4. **Determine the Circuit Element**:
- Since the current lags behind the voltage by π/2, this indicates the presence of inductance in the circuit. Therefore, the circuit must contain an inductor.

5. **Conclusion**:
- Based on the phase difference provided, the correct answer is that the circuit contains an inductor.

### Final Answer:
The circuit will contain an **inductor**.

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