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Capacitors coursework question

  1. Feb 20, 2007 #1
    Ok here a scanned photo oh my worksheet for physics. I tried and used what I knew for equations to solve. After looking at other sample problems, I am not sure how to find part b and c of the problem. I think I went wrong somewhere. Could someone take a look and guide me in the right direction. ty :smile:

  2. jcsd
  3. Feb 20, 2007 #2
    Part a looks okay.
    Part b, you assumed that there is 24 v across the cap of interest, is this correct? Think about kirchhoffs laws.
  4. Feb 20, 2007 #3
    I have no idea what kirchhoffs laws means, could someone explain it in simple terms
  5. Feb 20, 2007 #4
    Sorry, usually you see k's laws by this point. Basically( in nontechnical terms) , any voltage gained in the circuit must be dropped elsewhere. So you have an emf, or battery if you like, that is rated at 24 volts. This voltage is dropped across the capacitors. How much is dropped is given by the definition of capitance-> c = q/(delta v). Using the equivalent capacitance of each set of caps in parallel will tell you how much voltage is dropped by each pair. Devices in parallel by definition have the same voltage across them.
    Really, you should look up kirchhoff's laws, there is too much to explain here.
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