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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Physics => Topic started by: CorkedBoard on July 24, 2021, 11:58:39 am

Title: Question about Lenz’s law in DC motors
Post by: CorkedBoard on July 24, 2021, 11:58:39 am

Just wondering,
I know that in AC and DC generators, the movement of the current is used to create an opposed rotational force to what is causing it to rotate such as a wind turbine (due to Lenz’s Law).

What I am confused about is whether this also applies to DC motors. Does Lenz’s law apply to DC motors is it not relevant to DC motors?
Regards

Title: Re: Question about Lenz’s law in DC motors
Post by: fun_jirachi on July 24, 2021, 12:15:46 pm

Lenz's law will always apply in some capacity if there is a current induced due to a change in a magnetic field, primarily due to (and/or as an extension to the Law of Conservation of Energy).

It might be helpful to read about back EMF (and deduce for yourself why this works the way it does).