Homework Help: Equivalent resistance with a short circuit

1. Sep 7, 2014

sun18

1. The problem statement, all variables and given/known data
Find the equivalent resistance of the circuit shown below.

2. Relevant equations
R=$\Sigma_{i}$R$_{i}$
1/R=$\Sigma_{i}$1/R$_{i}$

3. The attempt at a solution
I'm having a lot of trouble understanding how this circuit can be simplified. All I see is a big short circuit where the only element that matters is R$_{4}$. What I tried was considering R$_{2}$ and R$_{3}$ as being in parallel, but I still see a short circuit happening. I don't think I understand how short-circuits behave, because I don't think the equivalent resistance is simply R$_{4}$. Any guidance would be greatly appreciated (also sorry for the terrible drawing)

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2. Sep 7, 2014

Staff: Mentor

Hi sun18, Welcome to Physics Forums.

Your intuition is correct; The subnetwork consisting of R1 through R3 is bypassed by the wire running from the top terminal to R4. A short circuit is equivalent to a resistance of zero Ohms, so anything in parallel with it is effectively bypassed (A zero Ohm resistance in parallel with any other resistor value is zero).

3. Sep 7, 2014

sun18

Thanks so much for the response gneill. I guess I was overthinking it instead of concluding the obvious.