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    Been doing past papers and just general questions I've found; one of the things that always seems to come up is eddy currents. Easy enough, but different mark-schemes and different websites seem to explain inefficiency of transformers in different ways.

    What I've got is:
    -flux in core
    -emf in core
    -current in core

    then A
    -energy wasted as heat

    or B
    -flux induced in core
    -opposes the original change of flux (Lenz's law)
    -reduces flux

    In the mark-schemes I've seen both come up and using the wrong one gets 0 marks... I'm kind of unsure what to do, write both?
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    (Original post by zackdove)
    Been doing past papers and just general questions I've found; one of the things that always seems to come up is eddy currents. Easy enough, but different mark-schemes and different websites seem to explain inefficiency of transformers in different ways.

    What I've got is:
    -flux in core
    -emf in core
    -current in core

    then A
    -energy wasted as heat

    or B
    -flux induced in core
    -opposes the original change of flux (Lenz's law)
    -reduces flux

    In the mark-schemes I've seen both come up and using the wrong one gets 0 marks... I'm kind of unsure what to do, write both?
    I would put both tbh, I'm doing A2 OCR B physics aswell and their mark schemes are too picky. So if I was answering that question, I would put both
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    (Original post by SheLikeTheMango)
    I would put both tbh, I'm doing A2 OCR B physics aswell and their mark schemes are too picky. So if I was answering that question, I would put both
    Yeah I've realised thats how the markschemes work now; As long as you write one correct answer you still get the marks unless you write another contradictory answer
 
 
 
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