Electro Magnetic Induction And Alternating Currents Question 532
Question: When the current in a coil changes from 8 ampere to 2 ampere in $ 3\times {{10}^{-2}} $ second, the e.m.f. induced in the coil is $ 2\ volt $ . The self-inductance of the coil (in millihenry) is [MNR 1991; UP SEAT 2000; Pb PET 2004]
Options:
A) 1
B) 5
C) 20
D) 10
Show Answer
Answer:
Correct Answer: D
Solution:
$ e=-L\frac{di}{dt}\Rightarrow 2=-L( \frac{8-2}{3\times {{10}^{-2}}} ) $
$ \Rightarrow L=0.01\ H=10\ mH $