ECN Forum Forums Technical Discussion Electrical Theory and Applications how the polarity of inductor changes?

when we apply the D.C source to inductor,current will rise in inductor. but when we switch off the supply how inductor will change its polarity?

The current in the inductor doesn't change polarity, but the voltage across it does. The voltage is proportional to the change in the magnetic flux, so a decreasing flux has the opposite sign (polarity) from an increasing flux.

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