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help pls - i know its physics but im really desperate and hopw that sum of u do physi watch

    • Thread Starter

    please help - the spec says - a qualitative understanding of the back emf in motors. these re simple motors i believe.
    if anyone has any idea pls let me know cos i don't - thanks so much :confused:

    The motor rotates because there is a current moving in a magnetic field, and its direction determined by fleming's left hand rule. However, whenever a coil of wire moves in a megnetic field an emf is generated (as in a dynamo), and the direction of current induced is determined by the right hand rule . Thus when a motor spins, some emf is induced in the opposite direction to the input current, which is the back emf.
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