How does a resistor exactly reduce current flow in a circuit

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A resistor reduces current flow in a circuit by acting as a physical obstruction, limiting the movement of electrons. The resistance of a material is determined by its number of free electrons, with metals typically having lower resistance due to their abundance of free electrons. Electron movement is significantly slower than commonly perceived, with drift velocities ranging from millimeters to centimeters per second, while electromagnetic waves can travel near the speed of light. In both DC and AC circuits, the initial pulse of electricity is what propagates quickly, not the actual flow of electrons. Understanding these principles clarifies how resistors function within electrical circuits.
tor2006
Greeting .

It is clear to me that the resistor represents a physical obstruction to the passing current I do not know how exactly it works and I will try to show what I was really interested in the diagram.
 

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tor2006 said:
Greeting .

It is clear to me that the resistor represents a physical obstruction to the passing current I do not know how exactly it works and I will try to show what I was really interested in the diagram.
Current is like a bicycle chain --- all parts move at the same time. Actual electron movement is MUCH slower than you probably imagine. Google "drift current"
 
You may also notice that the number of electrons entering and leaving the battery are equal. So one side cannot flow faster than the other.
 
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tor2006 said:
Greeting .

It is clear to me that the resistor represents a physical obstruction to the passing current I do not know how exactly it works and I will try to show what I was really interested in the diagram.

Resistance is a property of the material; e.g. Metals have a lot of free electrons, which means in general they have less resistance. Higher the resistance, lesser the number of free electrons in the material. These electrons are what carries the current. (at speed of light)
 
Frenemy90210 said:
Resistance is a property of the material; e.g. Metals have a lot of free electrons, which means in general they have less resistance. Higher the resistance, lesser the number of free electrons in the material. These electrons are what carries the current. (at speed of light)
No, electricity in conductors does not travel at c but at a slightly lower speed.

https://www.physicsforums.com/threads/electricity-doesnt-move-at-the-speed-of-light.5367/
 
phinds said:
No, electricity in conductors does not travel at c but at a slightly lower speed.

https://www.physicsforums.com/threads/electricity-doesnt-move-at-the-speed-of-light.5367/

No, they travel even slower ... Drift velocity is mm to cm / sec depending on conductor and magnitude of the current

https://en.wikipedia.org/wiki/Drift_velocity

The only thing that travels at near the speed of light is the pulse of the EM wave along the outside of the conductor

In a DC circuit, it is a single initial pulse when the circuit is switched on. In an AC circuit, it is a cycling pulse at the rate of the AC signal frequencyDave
 
davenn said:
The only thing that travels at near the speed of light is the pulse of the EM wave along the outside of the conductor
A longitudinal wave of compression and rarefaction must also travel through the outer electrons in the conductor. Or not?
 
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davenn said:
No, they travel even slower ...
I specifically was not talking about electrons and drift velocity but electricity (that is, current)
 
phinds said:
I specifically was not talking about electrons and drift velocity but electricity (that is, current)

basically the same thing ... current is the flow/movement of charge (s), those charges are the electrons

As I said, Only the EM wave travels at near light speed :smile:
 

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