Question

A coil of 40 henry inductance is connected in series with a resistance of 8 ohms and the combination is joined to the terminals of a 2-volt battery. The time constant of the circuit is

• A. $\frac{1}{5}$ seconds
• B. 40 seconds
• C. 20 seconds
• D. 5 seconds

Answer 1

Answer: (D)

5 seconds

Answer 2

τ=LR=$\frac{40}{8}$=5 sec