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Question
The co-efficient of mutual induction between primary and secondary coil is 2H. Calculate induced e.m.f. if current of 4A is cut off in 2.5 x 10-4 seconds
Solution
Here, the co-efficient of mutual induction, M = 2H
4A is cut-off in 2.5 × 10-4 seconds.
Induced e.m.f., E = `M(di)/(dt)`
`therefore E = 2Hxx(4A)/(2.5xx10^-4)`
`therefore E = 3.2 xx 10^4V`
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