Voltage across resistors in series and parallel

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Discussion Overview

The discussion revolves around the behavior of voltage across resistors in series and parallel configurations within electrical circuits. Participants explore the principles of voltage and current relationships in these setups, seeking to clarify misconceptions related to electrostatics.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about the voltage across a bulb and a resistor in parallel, questioning the relationship between voltage and current when the resistances may differ.
  • Another participant asserts that branches in parallel have the same voltage, but does not clarify the implications for current.
  • A follow-up question is posed regarding whether the same principle applies to resistors in series, specifically if their voltages would be equal regardless of their resistance values.
  • Another participant reiterates that in parallel configurations, voltage remains the same, while in series configurations, current is consistent across components.

Areas of Agreement / Disagreement

Participants generally agree that in parallel circuits, voltage is the same across all branches, but there is uncertainty regarding the behavior of voltage in series circuits, with some questions remaining unresolved.

Contextual Notes

There is a lack of clarity regarding the specific conditions under which voltage and current relationships hold true, particularly in the context of differing resistor values in series and parallel configurations.

TrolliOlli
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So I must be missing some crucial knowledge in my knowledge of electrostatics because I simply don't understand how this works. I'm given a circuit like this:

[PLAIN]http://img3.imageshack.us/img3/8730/circuiti.png

and I find out the voltage across bulb B is the same as that across the 10 ohm resistor.

I was under the impression that, since we know V = IR and we know the current across B is the same as the current across the 10 ohm resistor the Voltage would be different assuming B has a resistance other than 10 ohms. What am I missing here?
 
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The voltage is the same, not necessarily the current. Branches in parallel have the same voltage.
 
Doc Al said:
The voltage is the same, not necessarily the current. Branches in parallel have the same voltage.

Would that also apply to two resistors in series? If I simply had a battery with two resistors in series would their voltage be equal regardless of whether or not their resistors were equal?
 
TrolliOlli said:
Would that also apply to two resistors in series? If I simply had a battery with two resistors in series would their voltage be equal regardless of whether or not their resistors were equal?
Things in parallel have the same voltage; things in series have the same current.
 

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