B Solving a Circuit: Neglecting the 1 Ohm Resistor

[Neon32]

I want to know why in this problem in the solution, he disregarded the 1 ohm resistor and found the equivalent resistance of 6 and 3 ohms right away.

https://imgur.com/a/efG11

 

[Nugatory]

What is the current through that resistor? What does that tell you about the voltage drop across it?

 

[Neon32]

What is the current through that resistor? What does that tell you about the voltage drop across it?

I don't know the current through that resistor. Actually I don't know the current on any of the resistors so I'm not sure what you are trying to say.

 

[anorlunda]

Current has to come from someplace and go to another. If there was current in the 1 ohm resistor, where would it go?

 

[Neon32]

Current has to come from someplace and go to another. If there was current in the 1 ohm resistor, where would it go?

it will go to V0. there is a voltage V0

 

[anorlunda]

No, you are misinterpreting the diagram. Those circles at the ends of the wires near V0 depict the terminals of an open circuit. Zero current goes to V0.

 

[Neon32]

No, you are misinterpreting the diagram. Those circles at the ends of the wires near V0 depict the terminals of an open circuit. Zero current goes to V0.

So you mean if the current doesn't go anywhere after passing through the resistor so we disregard it? we consider the current is equal 0?

 

[anorlunda]

So you mean if the current doesn't go anywhere after passing through the resistor so we disregard it? we consider the current is equal 0?

Yes. If we know the current in the resistor is zero, then the resistor can be removed or ignored without changing the circuit.

 

[Neon32]

So you mean if the current doesn't go anywhere after passing through the resistor so we disregard it?

Yes. If we know the current in the resistor is zero, then the resistor can be removed or ignored without changing the circuit.

Got it. Thank you, appreciated.