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Question
In a given coil of self-inductance of 5 mH, current changes from 4 A to 1 A in 30 ms. Calculate the emf induced in the coil.
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Solution
Self inductance, L=5 mH=5×10−3 HChange in current,
dI=(1−4)=−3 A
Change in time, `dt=30 ms=30×10−3 s`
The emf induced in the coil is given by ` e=−L(dI)/(dt)`
`⇒e=((−5xx10^(−3) )xx(−3))/(30×10^(−3))`
`⇒e=0.5 V`
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