What is the opposition to the flow of alternating current produced by a magnetic field with generated back voltage (EMF) called?

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Multiple Choice

What is the opposition to the flow of alternating current produced by a magnetic field with generated back voltage (EMF) called?

Explanation:
Opposition to AC flow produced by a magnetic field with back EMF is inductive reactance. When current changes in an inductor, the magnetic field changes and the changing flux induces a back EMF that resists the change in current, per Lenz’s law. This resistance to current in AC is a reactive effect, not a simple resistance, and it grows with frequency and with the inductance: X_L = 2πfL. As a result, in a circuit with inductance, current lags voltage. The other phenomena shown by the other options involve capacitors, coupling between coils, or losses in the core, none of which describe this magnetic-back-EMF opposition.

Opposition to AC flow produced by a magnetic field with back EMF is inductive reactance. When current changes in an inductor, the magnetic field changes and the changing flux induces a back EMF that resists the change in current, per Lenz’s law. This resistance to current in AC is a reactive effect, not a simple resistance, and it grows with frequency and with the inductance: X_L = 2πfL. As a result, in a circuit with inductance, current lags voltage. The other phenomena shown by the other options involve capacitors, coupling between coils, or losses in the core, none of which describe this magnetic-back-EMF opposition.

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