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Homework Help: Light bulb brightness in a circuit

  1. Jun 3, 2010 #1
    ok revision question fo me, just wanna check my reasonning.

    which of te bulbs on the circuit of the attatched file will shine more brightly?

    i think p.............because s and t r and q are in parrellel which is resistance 1/Rs+Rt+1/Rr+Rq
    where Rp is the sum of the resistance of 1/Rs+Rt+1/Rr+Rq over 1 +1/Rp

    the resistance of the lower part of the parellel circuit Rs,Rt,Rr and Rq will be greater than the resistance of Rp.

    Is this answer and reasoning correct?

    many thanks

    Attached Files:

    Last edited: Jun 3, 2010
  2. jcsd
  3. Jun 3, 2010 #2
    The one that will glow the brightest will give off the most joules of energy per second, assuming that all the light bulbs are the same (ie same amount of electrical energy converted to light energy).

    So which resistor is "giving off" the most joules of energy? there is a name for joules of energy per second, do you know what it is and how it is calculated?
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