Electro Magnetic Induction And Alternating Currents Question 574
Question: If in a coil rate of change of area is 5 m2/milli second and current become 1 amp from 2 amp in $ 2\times {{10}^{-3}},sec. $ If magnitude of field is 1 tesla then self inductance of the coil is [RPET 2000]
Options:
A) 2 H
B) 5 H
C) 20 H
D) 10 H
Show Answer
Answer:
Correct Answer: D
Solution:
$ N\varphi =Li\Rightarrow \frac{Nd\varphi }{dt}=\frac{Ldi}{dt}\Rightarrow NB\frac{dA}{dt}=\frac{Ldi}{dt} $
$ \Rightarrow \frac{1\times 1\times 5}{{{10}^{-3}}}=L\times ( \frac{2-1}{2\times {{10}^{-3}}} )\Rightarrow L=10H $
