Voltage and Resistors in Series

[nDever]

Hey guys,

I have a question about resistors in series. If resistors dissipate power which result in a voltage drop, then why is the voltage at the resistor the same as the supply voltage?

 

[FlexGunship]

I have a question about resistors in series. If resistors dissipate power which result in a voltage drop, then why is the voltage at the resistor the same as the supply voltage?

I assume you are talking about a resistor connected directly across the voltage supply?

Your supply defines the relative voltage across two nodes. Your voltage across the resistor is the same because its directly connected to the supply. An idealized wire doesn't have impedance and therefore doesn't cause a voltage drop, so there is no drop prior to the resistor (nor after). If you define your voltage supply as (V) and solve for zero drop across the idealized wire (R=0), you will find that the voltage across your resistor is (V - 0V).

 

[Hootenanny]

Hey guys,

I have a question about resistors in series. If resistors dissipate power which result in a voltage drop, then why is the voltage at the resistor the same as the supply voltage?

Welcome to Physics Forums.

What do you mean the voltage "at" the resistor? A voltage can only be measured between two points. Do you mean the voltage across (i.e. the potential different between the two terminals of the resistor) the resistor?

 

[nDever]

Welcome to Physics Forums.

What do you mean the voltage "at" the resistor? A voltage can only be measured between two points. Do you mean the voltage across (i.e. the potential different between the two terminals of the resistor) the resistor?

Thanks for the welcome.

Yes. I do mean the voltage across the resistor.