Time constant of an inductive circuit

Time constant (τ) of an inductive circuit is defined as the time required for the current to reach approximately 63.2% of its final steady value after a sudden change in voltage.

The formula for the time constant in an RL (Resistor–Inductor) circuit is:

τ = L / R

Where:
L = Inductance in Henry (H)
R = Resistance in Ohms (Ω)

From the formula, we can see that:
1. If inductance (L) increases, the time constant increases.
2. If resistance (R) decreases, the time constant increases.

Therefore, the time constant increases with increase of inductance and decrease of resistance.

Correct Answer: Option A