(adsbygoogle = window.adsbygoogle || []).push({}); Simplifying "Complex" Resistor Circuits

1. The problem statement, all variables and given/known data

Question 1:

I have an E&M test coming up and I'm having trouble simplifying complex circuits. Our teacher told us something about "pinching" the wires which I didn't really understand. I found the following link "http://www.allaboutcircuits.com/vol_1/chpt_7/3.html". I got the right solution for the homework problem using it but is this method reliable? Does it always work? Are there any other suggestions for tackling this type of problems?

Question 2

The attached problem is from homework. The question is what would an ohmmeter read between a and b. I don't understand these questions much. I simplified it to what is shown in the second attached image without much trouble. Now my intuition tells me that I should add these three remaining resistors (in series) and that's the answer (40.3 Ω) but that's apparently wrong. My teacher says that I should add the 7 Ω and 23.3 Ω together (in series). Then take the resulting 30.3 Ω resistor and add it with the 10 Ω (in parallel) and that gives 7.5 Ω, which is the correct answer. Can someone explain this to me please?

Please excuse the weird looking lines in the diagrams. I'm new to Visio. Thanks.

2. Relevant equations

3. The attempt at a solution

Attached.

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# Homework Help: Simplifying Complex Resistor Circuits

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