(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Through a fluorescent tube of a diameter of 3cm cross the transversal secion per second 2x10^18 electrons and 0.5x10^18 positive ions (with charge +e) What is the current that goes through the tube?

2. Relevant equations

I=Vd*n*e*A

3. The attempt at a solution

I have Vd*n for the electrons that is 2x10^18

I have Vd*n for the electrons that is 0.5x10^18

I calculate the area as 2pi(3/2)^2

And I have the charge of an electron

I know that talking about current you don't have to make a distinction between positive and negative charges, but that's theroy. In practice I don't know whether to add the current generated by the positive charges with the other one, to substract them, or what?

How am I supposed to proceed in this cases?

Thanks in advance.

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# Homework Help: Calculating the current

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