Finding the number of electrons?

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In summary, the conversation discusses finding the number of electrons passing through a wire with only resistance given. It is suggested to use the equations V=IR, I=dQ/dt, and n=Q/e for direct substitution. There is a question about whether there is another way to solve this without assuming a value for voltage, as well as a reminder to consider the relationship between voltage and time. The conversation also mentions that the problem involves the number of electrons passing through a certain resistance in one second. Finally, a suggestion is made to use the equation n=(V/dt)R/e, assuming V/dt=1, but there is uncertainty about how this would work dimensionally.
  • #1
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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  • #2
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.
 
  • #3
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.
 

FAQ: Finding the number of electrons?

How do you find the number of electrons in an atom?

To find the number of electrons in an atom, you can look at the atomic number of the element. This number represents the number of protons in the atom, which is also equal to the number of electrons.

Can the number of electrons in an atom change?

The number of electrons in an atom can change through a process called ionization, where an atom gains or loses electrons. However, the number of electrons in a neutral atom (equal number of protons and electrons) remains constant.

How does the number of electrons affect an atom's properties?

The number of electrons in an atom determines its chemical and physical properties. The arrangement of electrons in an atom's outermost energy level, also known as the valence electrons, determines how an atom will interact with other atoms to form chemical bonds.

How do you determine the number of electrons in an ion?

An ion is an atom that has gained or lost electrons, resulting in a net positive or negative charge. To determine the number of electrons in an ion, you can look at the ion's charge - a positive ion will have fewer electrons than its neutral atom, while a negative ion will have more electrons.

Can the number of electrons in an atom be greater than the number of protons?

In a neutral atom, the number of protons is always equal to the number of electrons. However, in an ion, the number of electrons can be greater or smaller than the number of protons, resulting in a net charge.

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