A) 40 V
B) 400 V
C) 0.4 V
D) 100 V
Correct Answer: D
Solution :
From Faradays law of electromagnetic induction, the induced emf is given by \[e=-L\frac{di}{dt}\] where L is coefficient of self-induction,\[\frac{di}{dt}\]is rate of change of current. Given, \[L=40\text{ }mH=40\times {{10}^{-3}}H,\] \[\frac{di}{dt}=\frac{10}{4\times {{10}^{-3}}}\] \[\therefore \] \[e=-40\times {{10}^{-3}}\times \frac{10}{4\times {{10}^{-3}}}\] Negative sign signifies Lenzs law. \[\Rightarrow \] \[e=100\text{ }V\]You need to login to perform this action.
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