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Question
In an experiment, two coils c1 and c2 are placed close to each other. Find out the expression for the emf induced in the coil c1 due to a change in the current through the coil c2.
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Solution
Suppose that a current I is flowing through the coil c2 at any instant. Flux linked with the coil c1 is given by
Φ ∝ I
Φ = MI ….. (i)
Where M is called coefficient of mutual induction
If ‘e’ is the induced emf produced in the coil c1, then
`e=(dphi)/dt=-d/(dt)(MI)=-M(dI)/dt`
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