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Homework Help: Current and Power

  1. May 15, 2007 #1

    tdk

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    1. The problem statement, all variables and given/known data
    the current through the toaster connected to a 120-V source is 8 A. What power is dissipated by the toaster?


    2. Relevant equations

    I=V/R

    3. The attempt at a solution

    v=120
    A=8
    I=(120)?
     
  2. jcsd
  3. May 15, 2007 #2

    berkeman

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    Staff: Mentor

    The relevant equation that you need is the Power in terms of the Current and Voltage. Are you familiar with that equation?
     
  4. May 15, 2007 #3

    chroot

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    You can't use I = V/R, because that equation does not contain any reference to power!

    If you assume P = V * I, then P = V^2 / R.

    - Warren
     
  5. May 17, 2007 #4

    tdk

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    is the equation i have to use p=I/V?
     
  6. May 17, 2007 #5

    chroot

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    That equation is not correct. I gave you the equation in my previous post, did you read it?

    - Warren
     
  7. May 17, 2007 #6

    tdk

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    yes i read your post, you said P = V^2 / R. But I dont know what R is
     
  8. May 17, 2007 #7

    chroot

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    So, you didn't read my post in entirety. I said specifically that

    P = V * I

    - Warren
     
  9. May 17, 2007 #8

    tdk

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    Ohh yeah, I'm sorry thats what I meant to say in my previous post. I understand now,Thanks for your help!
     
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