Finding the number of electrons?

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To find the number of electrons passing through a wire with only resistance given, one must use the relationship between voltage (V), current (I), and resistance (R) through Ohm's Law (V=IR). The current can be expressed as I = dQ/dt, where dQ is the charge and dt is the time interval. The number of electrons (n) can be calculated using the equation n = Q/e, where e is the elementary charge. The discussion highlights that while V and time (t) must be assumed, their specific values are less critical as long as they maintain a consistent relationship. The challenge lies in ensuring dimensional consistency when substituting values into the equations.
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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