Electric circuit problem, finding current through a resistor

AI Thread Summary
The discussion focuses on calculating the current through resistor R1 in a circuit with given resistances and a total current of 6.0 A. Resistors R2 and R3 are in parallel, and the entire setup with R1 is also in parallel. The relevant equations include Ohm's Law (V=IR) and rules for combining resistances in series and parallel. The user expresses confusion about how to determine the current through each resistor without additional voltage information. The solution involves finding the voltage across the parallel resistors and calculating the current through each based on that voltage.
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1. The diagram attached shows part of an electric circuit. What is the current through resistor R1?

To summarize:
I=6.0 A
R1 = 11.0 Ω
R2 = 33.0 Ω
R3 = 67.0 Ω

R2 and R3 are in parallel, and R1 and R2 and 3 are in parallel.

I know we aren't supposed to attach pictures of questions, but a diagram does make my question a lot easier to understand.


Homework Equations



V=IR
IT in series = I1=I2=I3
IT in parallel = I1+I2+I3
RT in series = R1+R2+R3
RT in parallel = [(1/R1)+(1/R2)+(1/R3)]-1

The Attempt at a Solution



Using the resistor laws, I can find resistance of R2 and 3 by (1/33+1/67)-1.

Using Kirchoff's Laws, I know that the resistance coming out has to equal the 6.0 A.

But I don't get how all this information is relevant. The question doesn't give me voltage or any other information and I don't know how to figure out how much current goes through each resistor.
 

Attachments

  • diagram.PNG
    diagram.PNG
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