Question

A solenoid with inductance L = 7 mH and active resistance R = 44 Ω is first connected to a source of direct voltage $V_0$, and then to source of sinusoidal voltage with effective value V = $V_0$. At what frequency of the oscillator will the power consumed by the solenoid be η = 5.0 times less than in the former case?​

Answer 1

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