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# n = I/e is this equation correct Watch

1. I'm retaking one module on AS physics, but I'm studying for it on my own and haven't seen my teacher in a while because I don't do A2 physics. But I remember he told me about this equation that you can use to find the number density. I don't have my book but I remembered this equation from my memory but I don't know if it's correct. So can someone please check it for me:

n = I/e

n being the number density and I being the current and e is the electronic charge (-1.6 x 10^-19)
2. In your formula, n is the number of electrons passing a point in one second, if thats what you want, then its fine.

Proof: If we have n electrons passing a point in a second, then each has a net charge e (using corrected current). that means I=ne, as I is the net charge passing a point in a second. Simply then, I/e=n
3. yes, that's correct

Advancing physics G491 OCR, by any chance?
4. (Original post by madfish)
yes, that's correct

Advancing physics G491 OCR, by any chance?
nope OCR G482
5. (Original post by celina10)
nope OCR G482
oh
6. I=nAvq

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