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#130643 - 09/17/06 10:46 PM how the polarity of inductor changes?
satishkumar Offline
Junior Member

Registered: 09/14/06
Posts: 5
Loc: hyd,ap,india
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?

#130644 - 09/21/06 05:24 PM Re: how the polarity of inductor changes?
John Crighton Offline

Registered: 05/16/05
Posts: 172
Loc: Southern California
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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