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In an unloaded transformer, the flux limiting the primary is 10 mWb and secondary is 30 mWb. The coefficient of coupling is ____________

In an unloaded transformer, the flux limiting the primary is 10 mWb and secondary is 30 mWb. The coefficient of coupling is ____________ Correct Answer 0.33

Φ11 = (1 – k) Φ1 Or, φ11 = φ1 – φ2 Or, φ11 = 30 – 10 = 20 mWb Now, 20 mWb = (1 – k) 30m Or, 0.67 = 1 – k Or, k = 0.33.

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