Equivalent resistance with a short circuit

AI Thread Summary
The discussion focuses on finding the equivalent resistance in a circuit with a short circuit. The user struggles to simplify the circuit, initially considering resistors R2 and R3 in parallel but is confused by the presence of a short circuit. It is clarified that the short circuit effectively bypasses the resistors R1 through R3, making their contribution negligible. The key takeaway is that the equivalent resistance is determined solely by R4, as the short circuit has a resistance of zero Ohms. Understanding the behavior of short circuits is essential for correctly analyzing such circuits.
sun18
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Homework Statement


Find the equivalent resistance of the circuit shown below.


Homework Equations


R=\Sigma_{i}R_{i}
1/R=\Sigma_{i}1/R_{i}

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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sun18 said:

Homework Statement


Find the equivalent resistance of the circuit shown below.


Homework Equations


R=\Sigma_{i}R_{i}
1/R=\Sigma_{i}1/R_{i}

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)

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