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Question
A long solenoid of length l, cross-sectional area A and having N1 turns (primary coil), has a small coil of N2 turns (secondary coil) wound about its center. Determine the Mutual inductance (M) of the two coils.
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Solution
`∅_2="N"_2"B"_1"A"`
∅2 = `"N"_2xx(μ_0"N"_1"I"_1)/"L"xx"A"`
∅2 = `(μ_0"N"_1"N"_2"A")/"L""I"_1`
Comparing with ∅2 = MI1
We get M2 = `(μ_0"N"_1"N"_2"A")/"L"`
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