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    Can someone explain this question to me, please? You're expected to use p=(v^2)/R . Since power is inversely proportional to resistance, as resistance increases, the mark scheme says, power decreases. The thing I don't understand is that if resistance is increasing, surely voltage is changing too - so how can we assume it's gonna stay constant?
    What about P=(I^2)R ? Why can't we assume current remains constant and say, as resistance increases, that power is also going to increase?

    I'm missing something here.

    Can someone explain this to me?
    Thanks.
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    (Original post by uuujac61)
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    Can someone explain this question to me, please? You're expected to use p=(v^2)/R . Since power is inversely proportional to resistance, as resistance increases, the mark scheme says, power decreases. The thing I don't understand is that if resistance is increasing, surely voltage is changing too - so how can we assume it's gonna stay constant?
    What about P=(I^2)R ? Why can't we assume current remains constant and say, as resistance increases, that power is also going to increase?

    I'm missing something here.

    Can someone explain this to me?
    Thanks.
    I hope this explains it for you!! If you've got any more questions ask away and I'll do my best to help!! Good luck for tomorrow!!Name:  physics.jpg
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    (Original post by Starkidemmax)
    I hope this explains it for you!! If you've got any more questions ask away and I'll do my best to help!! Good luck for tomorrow!!Name:  physics.jpg
Views: 54
Size:  203.0 KB
    Thank you!
 
 
 
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