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Homework Help: Problem 1 on current electricity

  1. Aug 10, 2010 #1
    1. The problem statement, all variables and given/known data

    the problem is attached to this post

    2. Relevant equations

    Req=1/R1+1/R2+..... for parallel and Req.=R1+R2+... for series... Kirchoff's law for Current and Potential to be applied

    3. The attempt at a solution
    completely lost ... pls help

    Attached Files:

    • p1.JPG
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  2. jcsd
  3. Aug 10, 2010 #2
    First you need to find current and voltage across [itex]R_{2}[/itex] as a function of time. Then you can find the generated heat by using the formula


    where [itex]V_{2}[/itex] and [itex]I_{2}[/itex] are the voltage and current across resistor [itex]R_{2}[/itex]. As you see, time goes from 0 to infinity (when the capacitor is fully charged).
  4. Aug 10, 2010 #3
    can u give me the answer???
  5. Aug 10, 2010 #4
    It's against the policy! You need to show some effort first.
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