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Question
What are the values of the self-induced emf in the circuit of the previous problem at the times indicated therein?
Solution
Given:-
Self-inductance, L = 1 H
For an inductor of self-inductance L, the emf induced is given by
`e = L(di)/(dt)`
(a) At t = 100 ms,
`(di)/(dt)=0.27"A/s"`
∴ Induced emf, `e = L(di)/(dt)=1xx0.27=0.27 V`
(b) At t = 200 ms,
`(di)/(dt)=0.036"A/s"`
∴ Induced emf `= L(di)/(dt)=1xx0.036=0.036V`
(c) At t = 1 s,
`(di)/(dt)=4.1xx10^-9"A/s"`
∴ Induced emf `=L(di)/(dt)=4.1xx10^-9V`
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