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Homework Help: Electricity - Resistance problem

  1. May 14, 2012 #1
    1. The problem statement, all variables and given/known data

    A 240 W television operates for 4.0 h a day in a typical Canadian home.
    Calculate the resistance of the television.

    2. Relevant equations

    1) I = Q/∆ t 2) E = QxV 3) P = (Q x V)/ ∆t 4) P = I^2 x R
    5) P = V^2/R 6) P = I x V 7) V = W/Q 8) V = E/Q
    9) Q = I x ∆t 10) R = V/I

    3. The attempt at a solution


    P = 240 W
    ∆t = 4 h = 14 400 s
    R = ?

    E = P x ∆t
    = 240 W x 14 400 s
    = 3 456 000 J

    I have done many practice problems but none such as this. I do not know where to go from here. There are many equations and I understand the most logical step next would be to either find the current or voltage and then using that value and Power to find the resistance. Or I can also find the value of Q and then using that and Power find either the current or voltage but not many values are given to do that.

    Please help, I have been at this question for quite a while now, going around in circles.
  2. jcsd
  3. May 15, 2012 #2
  4. May 15, 2012 #3


    User Avatar

    Staff: Mentor

    Hi gvhunting, Welcome to Physics Forums.

    How is power related to voltage and current? How about resistance? What are the common characteristics of the electricity supplied to homes in Canada?
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