A coil of inductance 1 H and resistance| EMI

JEE MAIN 2022

29-07-22 S1

Question

A coil of inductance 1 H and resistance $100 \Omega$ is connected to a battery of 6 v . Determine approximately .
(a) The time elapsed before the current acquires half of its steady – state value
(b) The energy stored in the magnetic field associated with the coil at an instant 15 ms after the circuit is switched on. (Given $\ln 2=0.693, \mathrm{e}^{-3 / 2}=0.25$ )

Select the correct option:

$\mathrm{t}=10 \mathrm{~ms} ; \mathrm{U}=2 \mathrm{~mJ}$

$\mathrm{t}=10 \mathrm{~ms} ; \mathrm{U}=1 \mathrm{~mJ}$

$\mathrm{t}=7 \mathrm{~ms} ; \mathrm{U}=1 \mathrm{~mJ}$

$\mathrm{t}=7 \mathrm{~ms} ; \mathrm{U}=2 \mathrm{~mJ}$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution