Calculate Power Absorbed by Each Element in Circuit

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    Absorbtion Power
AI Thread Summary
The discussion revolves around calculating the power absorbed by each element in a given circuit. The user identifies the current through I(s) as -3A, leading to a voltage of 66V across R(L) and a power absorption of 198W for that resistor. Confusion arises regarding the total resistance, with the user calculating the current through V(S) and finding a power absorption of 8/11 W. The user also calculates the power absorbed by I(S) as 198W, but questions the principle that power generated should equal power absorbed, indicating a potential discrepancy. Clarification and guidance on these calculations and the sign convention are requested.
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Homework Statement


For the following circuit, determine the power absorbed by each element
http://img401.imageshack.us/img401/840/pow2bl5.th.gif

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.
Cheers
 
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