Series resistors' output voltage

AI Thread Summary
The discussion centers around a statement in an electrical engineering textbook regarding series resistors and voltage dividers, which claims that the output voltage becomes undefined after combining two series resistors. Participants express confusion about this assertion, particularly regarding the context and meaning of the output voltage. It is suggested that the output voltage likely refers to the voltage across one of the resistors, but clarity is lacking without seeing the specific circuit diagram. Some contributors speculate that the statement may relate to scenarios involving internal resistance of a battery or load conditions. Overall, additional context from the textbook is deemed necessary to fully understand the claim.
Puglife
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In my electrical engineering textbook, in the section with voltage dividers, it says that after you combine two series resistors, then the output voltage can no longer be defined.

It then said that thus the equivalence was made strictly from a voltage source standpoint.

I do not understand why the output voltage would be no longer defined?

Your help much appreciated
 
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Puglife said:
In my electrical engineering textbook, in the section with voltage dividers, it says that after you combine two series resistors, then the output voltage can no longer be defined.

It then said that thus the equivalence was made strictly from a voltage source standpoint.

I do not understand why the output voltage would be no longer defined?

Your help much appreciated
The statements as you express them make no sense. Please quote it EXACTLY.
 
"after you combine two series resistors, then the output voltage can no longer be defined, thus the equivalence was made strictly from a voltage source standpoint." was a direct quote, and that's all it said. Their was a picture of a voltage source, and two series resistors right above that statement, but their was not defined output.

I am now assuming that the output is the voltage across resistor 2, because that is the only thing that makes any sense. I was just wondering if their was any like, laws, or insight that I was missing that I didnt understand
 
Puglife said:
"after you combine two series resistors, then the output voltage can no longer be defined, thus the equivalence was made strictly from a voltage source standpoint." was a direct quote, and that's all it said. Their was a picture of a voltage source, and two series resistors right above that statement, but their was not defined output.

I am now assuming that the output is the voltage across resistor 2, because that is the only thing that makes any sense. I was just wondering if their was any like, laws, or insight that I was missing that I didnt understand
Still doesn't make sense to me. I'd have to see the exact circuit to which they have applied that statement.
 
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phinds said:
Still doesn't make sense to me. I'd have to see the exact circuit to which they have applied that statement.

agree with phinds ... in particular the
after you combine two series resistors

DC circuit1.GIF


do you see any problem in this voltage divider ?
what do you think the voltage at point B is ?Dave
 
Can you scan that page of your book?

I'm wondering if the circuit comprises a battery with internal resistance and a load resistor? In that case if you combine the two resistors into one the node representing the battery terminal (aka output voltage) disappears.
 
Since the word "after" is not capitalized, does that mean it isn't the first word in the sentence...? Yes, additional context would help.
 
russ_watters said:
Yes, additional context would help.
Is essential, I think.
 
Puglife said:
after you combine two series resistors, then the output voltage can no longer be defined
I think it just means that the output voltage of a voltage divider can't be defined anymore after you combine the input resistor and the pull-down resistor in series. Like if you are solving a circuit that has a potentiometer in it or something, and need to combine the two sides of the pot to help you solve for some voltage other than the wiper voltage...
 
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