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Snoop06
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Homework Statement
Find the magnitude of the current in each branch of the circuit shown below, in which B1 = 3.86 V. Specify the direction of each current. (See attached image)
Homework Equations
V=IR
Kirchhoff's rule
The Attempt at a Solution
I labeled the points in the circuit starting in the lower left hand corner with A, then going up to the first junction B, and so on. Hopefully that makes my explanation make more sense.
I went ahead and chose E as my junction point (the junction point on the right) to give me the equation:
I2-I1-I3=0 or I1=I2-I3 (1)
Then I looked and the bottom loop, starting in the lower left hand corner going up. I got:
-I2R2-I3R3+E1=0 (2)
I next looked at the loop starting at point B and going up. I got:
-E2+I1R1+I2R2=0 (3)
I substituted equation 1 into equation 3 (giving me equation 4). I then multiplied both sides of equation 4 by 75 and both sides of equation 3 by 22 in order to get matching coefficients on the I3 term. I then subtracted those two equations to eliminate I3, giving me:
4618I2=459.92
I2=99.59mA which was incorrect.
I spent a lot of time on this and can't figure out where I went wrong, ant help is appreciated, and I will clarify anything that doesn't make sense. Thanks.