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Homework Help: Power Absorbtion

  1. Mar 28, 2008 #1
    1. The problem statement, all variables and given/known data
    For the following circuit, determine the power absorbed by each element
    http://img401.imageshack.us/img401/840/pow2bl5.th.gif [Broken]

    2. The attempt at a solution

    This sign convention stuff is realllly confusing me.
    Can someone give me some direction here?

    The current through I(s) is -3A, this implies that there is 3A flowing in the opposite direction yeah? Hence there is 3A flowing into R(L).

    The voltage across R(L) must then be: V[R(L)]= IR = 3 x 22 = 66V
    Hence the power absorbed by R(L) is: P[R(L)]= VI = 66 x 3 = 198W

    Here is where I start to get confused.
    The total resistance around the circuit must be 22 ohms right?

    The current through V(S) must then be I = V/R = 4/22 A
    P(S) = VI = 4 x (4/22) = 8/11 W

    The voltage through I(S) => V = IR = -3 x 22 = -66V
    Hence the power absorbed by I(S) is: P[I(S)] = VI = -66 x -3 = 198W

    Now I was under the impression that the Power generated must = Power abosrbed.
    That doesn't work here ...

    I'm not sure how much of this is right, but any help would be greatly appreciated.
    Last edited by a moderator: May 3, 2017
  2. jcsd
  3. Mar 29, 2008 #2
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