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Question
How does the mutual inductance of a pair of coils change when
(i) distance between the coils is increased and
(ii) number of turns in the coils is increased?
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Solution
(i) As, φ = MI, with the increase in the distance between the coils the magnetic flux linked with the secondary coil decreases and hence the mutual inductance of the two coils will decrease.
(ii) Mutual inductance of two coils can be found out by, M = μon1n2Al, i.e. M ∝ n1n2, so, with the increase in number of turns mutual inductance increases.
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