Question
A varying current in a coil changes from $10\, amp$ to zero in $0.5 \,sec$. If average $EMF$ is induced in the coil is $220 \,volts$, the self inductance of coil is....$H$
✓
Answer
(c) $|e|\, = L\frac{{di}}{{dt}} \Rightarrow 220$
$= L \times \frac{{10}}{{0.5}}$$ \Rightarrow L = 11\;H$
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