# How does a resistor exactly reduce current flow in a circuit

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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phinds
Gold Member
2019 Award
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"

tech99
Gold Member
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.

davenn
Frenemy90210
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)

phinds
Gold Member
2019 Award
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.

davenn
Gold Member
2019 Award
No, electricity in conductors does not travel at c but at a slightly lower speed.

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 frequency

Dave

tech99
Gold Member
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?

davenn
phinds
Gold Member
2019 Award
No, they travel even slower ...
I specifically was not talking about electrons and drift velocity but electricity (that is, current)

davenn