Determining Number of Electrons moving through a lamp.

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Dannytee
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The question I'm having trouble is:

A neon indicator lamp needs 90v to conduct. It then draws out 0.5mA.
Calculate the number of electrons moving through the lamp each second.

so...
Electron Charge - 1.6*10^-19
Voltage - 90
Current - 0.5mA​

Any sort of help would be helpful!
 
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What are the units on the electron charge Number?

What is the definition of current?

We need you do show some effort before more help can be given.
 
Recall, 1 electron has charge [itex]e=1.6×10^{-19} C[/itex], this means that 100 electrons would have charge [itex]100e[/itex], etc. Current [itex]I[/itex] is a measure of the change in charge per change in time. [itex]I=\frac{ΔQ}{Δt}[/itex]. You can think of current as a flow of electrons, and the current is a measure of how many electrons pass a fixed point per some time interval.

You know the current already as 0.0005 A, so you should be able to find the amount of charge after 1 second by setting [itex]Δt=1s[/itex] and solving for [itex]ΔQ[/itex] in the above equation. [itex]ΔQ[/itex], like I said can be thought of as an amount of electrons that passed some fixed point in 1 second.

Now ask yourself how many electrons do I have after 1 second, according to [itex]ΔQ[/itex]?

It's a simple ratio between how many electrons are in [itex]1e[/itex], and how many electrons are in your [itex]ΔQ[/itex]. It should look like this:

[itex]\frac{1.6×10^{-19}C}{1e}=\frac{ΔQ}{Ne}[/itex]. where N is the number of electrons that passed through the wire in 1 second.