Finding the number of electrons?

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SUMMARY

The discussion centers on calculating the number of electrons passing through a wire given only its resistance (R). The relevant equations include Ohm's Law (V=IR), the relationship between current and charge (I = dQ/dt), and the definition of electron quantity (n=Q/e). The participant explores the assumption that voltage (V) and time (t) can be manipulated, provided their product equals one, to derive the number of electrons. The conclusion emphasizes the need for a consistent relationship between these variables to accurately compute electron flow.

PREREQUISITES
  • Understanding of Ohm's Law (V=IR)
  • Knowledge of charge and current relationships (I = dQ/dt)
  • Familiarity with the fundamental charge of an electron (e)
  • Basic algebra for manipulating equations
NEXT STEPS
  • Study the derivation of current from voltage and resistance in electrical circuits
  • Learn about charge conservation in electrical systems
  • Explore dimensional analysis to validate equations in physics
  • Investigate practical applications of electron flow in conductive materials
USEFUL FOR

Students in physics or electrical engineering, educators teaching circuit theory, and anyone interested in understanding electron flow in conductive materials.

Arij
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Homework Statement


I was asked to find number of electrons passing through a wire giving only resistance.

Homework Equations


V=IR
I = dQ/dt
n= Q/e

The Attempt at a Solution


It's pretty straight forward, with direct substitution of the equations with the written order.
I could attempt this assuming V = 1 V but, is there another way to get this with only the value of R and I'm not seeing it??
 
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Do note that you also have to assume the time (t) as well as the voltage.
Therefore I believe the values of V and Time(t) don't matter so long as they have a relationship such that V times Time t gives you 1, given the relationship they have in the derived equation.
 
RememberYourAngles said:
Do note that you also have to assume the time (t) as well as the voltage.
Therefore I believe the values of V and Time(t) don't matter so long as they have a relationship such that V times Time t gives you 1, given the relationship they have in the derived equation.
forgot to mention that he did mention it's number of electrons passing through xx ohms in one second.

Correct me if wrong, your suggestion is:
n=Q/e=Idt/e= (V/R)dt/e=(V/dt) R/e and assuming V/dt = 1 but I'm not how does that work if I look at it dimensionally using units.
 

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