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Energy and Current

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

    What is the total energy dissipated as heat in a resistor of resistance R = 80.0 Ω when a current of I = 0.09 A passes through it for 1 minute?

    2. Relevant equations

    3. The attempt at a solution

    From the given values I can work out the potential difference, but I'm stuck here because I don't know what formula to use with energy in it. But I know that electric power can be found from P=IV=I2R, but I don't know how this helps to find energy. Of course I know that [tex]P=\frac{dU}{dt}[/tex], but I don't see how to solve for the energy... :confused:
  2. jcsd
  3. Oct 1, 2010 #2
    It seems you have the answer hiding right in front of you...

    If you know that the power drop across a resistor is (I^2)(R) then you can calculate that given the values.

    Next if you assume that it drops all that power through heat 'U' over that 1min and you know that P=U/t then...
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