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left hand and right hand rule??? watch

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    when do you use the left hand rule and when do you use the right hand rule? my teacher said you use the left for when doing a motor but what would you class as a motor?
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    generally use right hand for direction of induced emf's (Lenz's Law)
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    I gave up physics since AS and am operating on GCSE level knowledge, so ignore me if I make no sense...

    left hand rule is used to find force
    right hand rule is used to find current (I)

    I'll go away now and back to chemistry (much safer territory for me!)

    selkie
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    use the left hand rule with motors, and the right hand rule with dynamos.

    motors are machines that change electromagnetic energy into kinetic energy, i.e. currents and voltages into motion; dynamos are machines that change kinetic energy into electromagnetic energy, i.e. motion into voltages and currents.

    this is basically what others have said, but here are my revision notes on hand rules:

    HAND RULES

    first finger field
    second finger current
    thumb motion

    Fleming’s Left Hand Rule
    Used when a current from an external source flows through a conductor in a magnetic field, resulting in a force.

    e.g. motor
    motors drive cars and we drive on the left

    Fleming’s Right Hand Rule
    Used when an external force produces a motion on a conductor in a magnetic field, inducing a current to flow in the conductor.

    e.g. generator/dynamo

    Other Right Hand Rule
    Point thumb in direction of current; fingers show direction of magnetic field.

    You get a “thumbs up” when you are right!
 
 
 
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