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Sorry, I know I just posted a question but I picked up a textbook on circuit analysis over the summer just to teach myself some things and the examples during the chapter differ quiet a bit from the problems that they give you at the end of the chapter.
In the picture, it is asking to solve for E, R1, and I3.
I assume to find the voltage supply I would have to use E=Is (Rt) ... Would "Is" be 12.3 A since the sum of the current going in equals the sum of the current going out?
If it is... how would I find Rt if I don't know the value of R1. And how do you find the value of R1 if you do not know the value of Rt? Once I figure either one of the values out, I'd plug it into : 1/Rt= 1/R1 + 1/R2 + 1/R3
In my book I found a formula that said: I2 = (R1/ R1 + R2) I_{t}. When it was presented, that was only dealing with two resistors. Since here there are three resistors, would I thought it would be be : I3 = (R2/ R2+R3) I_{t} ? However, when I do that, I get the wrong answer...
Thank you in advance.
The answers are supposed to be:
E= 36 V
R1= 24 ohms
I3 = 9 A
https://mail.google.com/mail/u/0/?ui=2&ik=acf3e731ea&view=fimg&th=155a3589fadd93df&attid=0.1&disp=emb&realattid=155a358827f9aac4a5a1&attbid=ANGjdJvjYlOyzDVH70sHSoTjz6hteiONQ0F691wKGZQh_nGTJeWgQX0ewEbyGgVlvTolKswPfuL35am15crjzvOHsCBHsYIf3S_7a7bTSJ_rtS43WMmOUQt44Ilyg&sz=s0l75ft&ats=1467326257373&rm=155a3589fadd93df&zw&atsh=1
In the picture, it is asking to solve for E, R1, and I3.
I assume to find the voltage supply I would have to use E=Is (Rt) ... Would "Is" be 12.3 A since the sum of the current going in equals the sum of the current going out?
If it is... how would I find Rt if I don't know the value of R1. And how do you find the value of R1 if you do not know the value of Rt? Once I figure either one of the values out, I'd plug it into : 1/Rt= 1/R1 + 1/R2 + 1/R3
In my book I found a formula that said: I2 = (R1/ R1 + R2) I_{t}. When it was presented, that was only dealing with two resistors. Since here there are three resistors, would I thought it would be be : I3 = (R2/ R2+R3) I_{t} ? However, when I do that, I get the wrong answer...
Thank you in advance.
The answers are supposed to be:
E= 36 V
R1= 24 ohms
I3 = 9 A
https://mail.google.com/mail/u/0/?ui=2&ik=acf3e731ea&view=fimg&th=155a3589fadd93df&attid=0.1&disp=emb&realattid=155a358827f9aac4a5a1&attbid=ANGjdJvjYlOyzDVH70sHSoTjz6hteiONQ0F691wKGZQh_nGTJeWgQX0ewEbyGgVlvTolKswPfuL35am15crjzvOHsCBHsYIf3S_7a7bTSJ_rtS43WMmOUQt44Ilyg&sz=s0l75ft&ats=1467326257373&rm=155a3589fadd93df&zw&atsh=1
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