How is current same on both sides of a resistor

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Discussion Overview

The discussion centers on the behavior of electric current in relation to a resistor, specifically addressing why the current remains the same on both sides of a resistor despite its resistance to electron flow. The scope includes conceptual explanations and analogies to clarify the relationship between current, resistance, and potential difference.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that if the current were not the same on both sides of the resistor, there would be a buildup of charge within the resistor.
  • Others argue that the analogy of water flowing through a hose illustrates that while a resistor reduces the potential of the current, the same amount of current must exit as enters.
  • One participant notes that the resistor does indeed resist the flow of electrons, which contributes to heating, but this does not affect the equality of current on both sides.
  • Another participant emphasizes that the analogy of water flow is valid, suggesting that pressure changes (analogous to voltage) occur while maintaining the same flow rate (current).
  • It is mentioned that larger resistors allow less current, but the principle that what goes in must come out remains true.

Areas of Agreement / Disagreement

Participants generally agree that the current remains the same on both sides of the resistor, but there is some contention regarding the implications of resistance and the nature of current flow.

Contextual Notes

The discussion includes various analogies and interpretations of current flow and resistance, which may depend on the definitions and assumptions about electrical behavior and analogies used.

Ayaan
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How come that the current is equal on both the sides.The resistor should decrease the rate of flow of electrons i.e. current.
 
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If they weren't the same then you would have a build up of charge inside the resistor.

It's like when water goes in one end of a hose it has to come out the other end.

The resistor reduces the potential of the current. It would be the same as having some restriction inside the water hose. The same water that goes in would come out but it would lose some pressure. The restriction would also slow down the flow of water.

The resistor does decrease the rate of flow. What goes in still has to come out so the current is the same on both ends.
 
But I think that the resistor does resist the flow of electrons through it and that is why it gets heated up.
 
The usual analogy is water flowing thru a pipe: every drop of water entering a section also leaves that section, even if the size of the pipe changes ... which results in a pressur change. Pressure is analogous to voltage, while water flow is analogous to pressure.

The presence of resistance is thus like a change in pressure.

The analogy isn't perfect, but "what goes in must come out" is valid in both.
 
Ayaan said:
But I think that the resistor does resist the flow of electrons through it and that is why it gets heated up.

That is correct and has nothing to do with the fact that what goes in must come out. The resistor inhibits the AMOUNT of flow through it (larger resistors, in ohms, allow less current) but it is still true that however much goes in must come out.
 

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