Is the Resistance of this Easy Circuit Really Just 10 Ohms?

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The discussion centers on determining the resistance of a circuit, specifically questioning whether it is 10 ohms. It is concluded that the right-side resistor does not contribute to resistance due to having the same potential at both ends, resulting in zero current through it. Therefore, only the left resistor, which is 10 ohms, affects the total resistance. Participants clarify that a resistor in parallel with a short-circuit has zero equivalent resistance, while a resistor in series with a short-circuit retains its resistance value. The conversation emphasizes understanding current flow and resistance in circuit configurations.
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Is the resistance of this circuit 10 ohms?

http://img75.imageshack.us/img75/9229/littlecircuitro8.jpg

I can't prove anything to myself since the resistors aren't in parallel or series.

I do notice that the potential at the top of the right side resistor is the same as at the bottom... So by Ohm's law the current through it should be zero, and so it's just sitting there not resisting anything. Hence, only the left resistor provides resistance to the circuit and R_total = 10 ohms.

Am I correct? Because this just seems counter intuitive.Thanks!
 
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You are correct. I don´t see why do you say it is counter intuitive.
The equivalent resistance of a resistor in parallel with a short-circuit is a short circuit.
The equivalent resistance of a resistor in series with a short-circuit is the resistance of the resistor.
 
I dunno... It just seems to me like perhaps a little bit of the current would get through. :smile:

I guess if I looked at it as the current taking the path of least resistence, then yeah, I guess it's pretty intuitive. (Although, obviously, such an analogy couldn't extend to resistors in parallel)

Anyways... Thanks!
 
jmcgraw said:
I dunno... It just seems to me like perhaps a little bit of the current would get through. :smile:

I guess if I looked at it as the current taking the path of least resistence, then yeah, I guess it's pretty intuitive. (Although, obviously, such an analogy couldn't extend to resistors in parallel)

Anyways... Thanks!
Such analogy extends to resistors in parallel. The short-circuit has zero resistance, so all the current passes through it.
 

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