When current flowing in a coil of wire is stopped, what occurs?

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Multiple Choice

When current flowing in a coil of wire is stopped, what occurs?

Inductors resist changes in current. When the current through a coil is interrupted, the magnetic field around the coil changes quickly. This changing magnetic flux induces a voltage in the coil in a direction that tries to keep the current flowing—the self-induced EMF described by v = -L di/dt. So as you stop the current (di/dt becomes negative), the coil generates a voltage across its terminals, often large enough to cause arcing or to keep current flowing through another path. The coil doesn’t simply stop with no voltage, nor does it automatically reverse the current. The energy stored in the magnetic field is released as this induced voltage while the current decays.

Inductors resist changes in current. When the current through a coil is interrupted, the magnetic field around the coil changes quickly. This changing magnetic flux induces a voltage in the coil in a direction that tries to keep the current flowing—the self-induced EMF described by v = -L di/dt. So as you stop the current (di/dt becomes negative), the coil generates a voltage across its terminals, often large enough to cause arcing or to keep current flowing through another path. The coil doesn’t simply stop with no voltage, nor does it automatically reverse the current. The energy stored in the magnetic field is released as this induced voltage while the current decays.

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