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Homework Statement
A circuit is constructed with five resistors and a battery as shown. The battery voltage is V = 12.0 V. The values for the resistors are: R1 = 76.0 Ω, R2 = 149.0 Ω, R3 = 169.0 Ω, and R4 = 121.0 Ω. The value for RX is unknown, but it is known that I4, the current that flows through resistor R4, is zero.
Find I1
Homework Equations
Resistors in Series
Req = R1 + R2
Veq = V1 + V2
Ieq = I1 = I2
Resistors in Parallel
Req = (1/R1 + 1/R2)^1
Veq = V1 = V2
Ieq = I1 + I2
V = IR
The Attempt at a Solution
I know this has been asked elsewhere, but I read the other threads and couldn't get anything that helped me from them. I think I'm just having trouble visualizing the problem, and breaking the circuits into parts. I guess I'm having a lot of trouble visualizing how the energy travels through the circuit.
I just can't picture it at all. I started by combining the circuits into R13, R4, and R2x. I'm guessing that for I4 to be zero, I14 has to equal I2. Ahh... If I can see this problem built once, I'm sure I could do it over and over again. Help plz...
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