(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

[PLAIN]http://img156.imageshack.us/img156/2420/physicsm.jpg [Broken]

sorry for the image, i made it very quickly

in the following circuit find

a) the current in R

b) R

c) Emf

d) if we cut the circuit in X, then what would be the current that goes through the 28V battery

2. Relevant equations

V = I*R

3. The attempt at a solution

a)

i used the first kirchhof law and i found that

I3 = I2 - I1 = 6 - 4 = 2A

b)i used the second law of kirchhof and found that

Emf - 18 - 24 = 0 => Emf = 42 V

c)again i used the second law and found that

28 - 42 + 24 - I3*R = 0 => R = 5 Ω

d) i dont know how to do it, please help

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# Homework Help: Finding the current in a circuit

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