R circuit (pretty simple) need checked - full working - please

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The discussion revolves around verifying calculations for an electrical circuit involving resistors. The user calculated the current through various resistors and found the unknown resistor's value to be 11.3Ω, with a net voltage of 60V. They also computed the power loss, resulting in 207.6W, which they questioned as being unusually high. Responses confirmed the calculations were correct, providing reassurance to the user. The thread emphasizes the importance of accuracy in circuit analysis and power loss calculations.
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R circuit (pretty simple) need checked - full working - please!

Homework Statement



see attachment

Homework Equations


P=IV
P_loss=I^2 R
V=IR


The Attempt at a Solution


ok
36=I^2*12

I_12Ω=√3 A
V=20.8V
That is the same for the 3 resistors in parallel (I hope)
so I18Ω=1.15A
I36Ω=0.577A
the sum of these will give me the current through the unknown resistor
Iunknown=3.46A
net voltage = 60
60=Vunknown + 20.8
Vunknown=39.2V
V=IR
R=11.3Ω

can someone please check this - wouldn't ask if I dint need it.
 

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Your answer is correct.
 


Sorry, I forgot the second half of the question,

P_loss=I^2 R
P=〖3.46〗^2*((1/12+1/18+1/36)^(-1)+11.3)
P_loss=207.6W
This seems big to me, could you please check that too.
 


pat666 said:
Sorry, I forgot the second half of the question,

P_loss=I^2 R
P=〖3.46〗^2*((1/12+1/18+1/36)^(-1)+11.3)
P_loss=207.6W
This seems big to me, could you please check that too.

your answer is correct.
 

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