Calculating Current given the number of electrons and positive ions

AI Thread Summary
To calculate the current in the fluorescent tube, the total charge flow per second must be determined by considering both the electrons and positive ions. The charge of an electron is approximately -1.6 x 10^-19 coulombs, while positive ions carry a charge of +1.6 x 10^-19 coulombs. Given that 10 x 10^18 electrons and 2.5 x 10^18 positive ions are flowing, the total charge can be calculated by adding the absolute values of the charges from both particles. The current can then be found using the formula I = (delta Q)/(delta T), where delta T is 1 second. Thus, the total current in the tube is the sum of the contributions from both the electrons and positive ions.
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Homework Statement



In a fluorescent tube of diameter 3 cm, 10 *1018 electrons and 2.5 * 1018 positive ions (with a charge of +e) flow through a cross-sectional area each second. What is the current in the tube?


Homework Equations


Current is I = (delta Q)/(deta T)



The Attempt at a Solution



delta t is given as 1 second, but how do u calculate the change in charge given this information?
 
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Use the charge on the electron. Note that the positive ions will go the opposite way to the electrons, so you must add the two currents.
 
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