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Homework Help: Electric Potential and a capacitor

  1. May 16, 2005 #1
    Hi; Could someone please help me with the following question: A huge 4.0 F capacitor has enough stored energy to heat 2.5 kg of water form 21 degrees celsius to 95 degrees celsius. What is the potential difference across the plates? Could i use the equation: PE = 1/2 CV^2. However, I do not know how to solve for PE; how do I use the given temperatures and mass? Thank you for your help.
     
  2. jcsd
  3. May 16, 2005 #2
    I would use q=m*c*delta(T) to get the heat (Joules) transferred by the capacitor. m=the mass in grams of your water. c is the specific heat of water. delta T is the change in temperature. Then set that amount equal to your potential energy and solve for V....I think that's right
     
  4. May 16, 2005 #3
    thanks

    Thanks a lot for your help, I understand it now.
     
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