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Homework Help: Electric currents, etc etc

  1. Apr 23, 2005 #1

    I have a question to ask and was wondering if you guys could help me.

    5.) A computer has a 300-W power supply. If household voltage is 120 V, how much current will flow through the computer?
    A. 0.4 A
    B. 2.5 A
    C. 180 A
    D. 420 A
    E. 36,000 A

    I picked B. I used the equation Electric power= current x voltage and changed it so current=power/voltage...which is how i got 2.5 A.


  2. jcsd
  3. Apr 23, 2005 #2
    Yup, P = IV, so I = P/V = 300/120 = 2.5
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