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Question
A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil?
Solution
We are interested in the flux change associated with coil 2 as the current in coil 1 changes from 0 to 20 A.
∅2 = MI1
and Δ∅2 = MΔI1
Δ∅2 = 1.5 [20 – 0]
or Δ∅2 = 30 Wb
Here, the current is increasing, so the change in flux density will oppose the increase in current.
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