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Homework Help: How much energy is dissipated by the 25 ohm resistor?

  1. Oct 27, 2008 #1
    1. The problem statement, all variables and given/known data

    A 0.25 UF capacitor is charged to 50 V. It is then connected in series with a 25 ohm resistor and a 100 ohm resistor and allowed to discharge completely.

    2. Relevant equations
    P=I V=I^2R=(V^2)/R

    3. The attempt at a solution
    i'm not sure how to approach this problem. it hink there is formula i need that missing for calculating energy
  2. jcsd
  3. Oct 27, 2008 #2
    I can't remember exactly how it works, but if you go to allaboutcircuits.com you will find every bit of info for this type of problem. We actually used that site as the textbook when I took Electronics and Circuit Theory courses
  4. Oct 27, 2008 #3


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    Homework Helper
    Gold Member

    The energy stored in a capacitor is (1/2)CV^2. Initially, V=50 Volts. After the capacitor is completely discharged, the potential across it is clearly zero. so how much energy must have been dissipated?
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