Q. What is self inductance of a coil which produces 5V, when current in it changes from 3 A to 2 A in one millisecond?
A) 5000 H
B) 5 mH
C) 50 H
D) 5 H
Explanation
(b) $L = \ ?e = 5\ V,\frac{dI}{dt} = \ \frac{(2 - 3)}{10^{- 3}} = - 10^{3}\ As^{- 1}$
As $e = \ - L\frac{dI}{dt}$
$\therefore\ 5 = - L\left( - 10^{3} \right),\ L = \frac{5}{10^{3}}$H = 5mH
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.