An alternating e.m.f of 100 V is placed is applied to a circuit containing a resistance of `40 Omega ` and an inductance L in series . The current is found to lag behind the voltage by an angla a = `tan^(-1)`
The current flowing through the circuit is:

Explanation

To solve the problem, we need to find the current flowing through a circuit that consists of a resistance \( R = 40 \, \Omega \) and an inductance \( L \) in series, with an alternating e.m.f of \( 100 \, V \) applied. The current lags behind the voltage by an angle \( \alpha \).

### Step-by-Step Solution:

1. **Identify Given Values:**
- E.M.F (Voltage), \( V = 100 \, V \)
- Resistance, \( R = 40 \, \Omega \)
- The angle \( \alpha \) is given as \( \tan^{-1} \left( \frac{X_L}{R} \right) \).
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