Question

Calculate the time constant of an inductive circuit having resistance 5 ohm and inductance 10H.

(a) 2s

(b) 4s

(c) 5s

(d) 10s

I have been asked this question during a job interview.

This intriguing question originated from Growth in an Inductive Circuit in portion Inductance in a DC Circuit of Basic Electrical Engineering

Answer 1

The correct option is (a) 2s

For explanation I would say: We know that: Time constant = L/R

Substituting the values from the given question, we get a time constant = 2s.