MCQ
The average e.m.f. induced in a coil in which the current changes from $2$ ampere to $4$ ampere in $0.05$ second is $8$ volt. What is the self inductance of the coil ?
- A$0.1 \mathrm{H}$
- ✓$0.2 \mathrm{H}$
- C$0.4 \mathrm{H}$
- D$0.8 \mathrm{H}$
✓
Answer
Correct option: B.
$0.2 \mathrm{H}$
(b) $e=-L \frac{d i}{d t} \Rightarrow 8=L \frac{(4-2)}{0.05} \Rightarrow L=0.2 H$
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