Equivalent resistance with a short circuit

In summary, the circuit shown in the given problem has a short circuit that effectively bypasses the subnetwork consisting of R1 through R3. This means that the equivalent resistance of the circuit is simply R4, as a short circuit has a resistance of zero Ohms and anything in parallel with it is effectively bypassed.
  • #1
sun18
16
1

Homework Statement


Find the equivalent resistance of the circuit shown below.


Homework Equations


R=[itex]\Sigma_{i}[/itex]R[itex]_{i}[/itex]
1/R=[itex]\Sigma_{i}[/itex]1/R[itex]_{i}[/itex]

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[itex]_{4}[/itex]. What I tried was considering R[itex]_{2}[/itex] and R[itex]_{3}[/itex] 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[itex]_{4}[/itex]. Any guidance would be greatly appreciated (also sorry for the terrible drawing)
 

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  • #2
sun18 said:

Homework Statement


Find the equivalent resistance of the circuit shown below.


Homework Equations


R=[itex]\Sigma_{i}[/itex]R[itex]_{i}[/itex]
1/R=[itex]\Sigma_{i}[/itex]1/R[itex]_{i}[/itex]

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[itex]_{4}[/itex]. What I tried was considering R[itex]_{2}[/itex] and R[itex]_{3}[/itex] 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[itex]_{4}[/itex]. 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).
 
  • #3
Thanks so much for the response gneill. I guess I was overthinking it instead of concluding the obvious.
 

Related to Equivalent resistance with a short circuit

What is equivalent resistance?

Equivalent resistance is the resistance value that would produce the same current flow in a circuit as the combined resistances of all the individual components in the circuit.

What is a short circuit?

A short circuit occurs when there is a low resistance connection between two points in a circuit, causing a very high current flow. This can result in damage to the circuit and potential safety hazards.

What happens to equivalent resistance with a short circuit?

If a short circuit occurs in a circuit, the equivalent resistance will decrease significantly as the low resistance connection allows for a large amount of current to flow through the circuit.

How does a short circuit affect the overall circuit?

A short circuit can cause the overall circuit to malfunction or completely shut down due to the high current flow. It can also cause damage to components and potentially start a fire if not addressed properly.

How can equivalent resistance be calculated with a short circuit present?

When calculating equivalent resistance with a short circuit present, the short circuit can be treated as a wire with zero resistance. This means that the equivalent resistance can be calculated by simply adding the resistances of the remaining components in the circuit.

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