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

The electron beam emerging from a certain high-energy electron accelerator has a circular cross section of radius 1.20 mm.

(a) The beam current is 7.75 µA. Find the current density in the beam assuming it is uniform throughout.

correct check mark A/m2

(b) The speed of the electrons is so close to the speed of light that their speed can be taken as 300 Mm/s with negligible error. Find the electron density in the beam.

correct check mark m-3

(c) Over what time interval does Avogadro's number of electrons emerge from the accelerator?

s

2. Relevant equations

[tex]J=I/A[/tex]

[tex]I_{avg} = nqv_{d}A

3. The attempt at a solution

Part a and b are straight forward.

For part a I have: 1.71 A/m^2

For part b I have: 3.565 x 10^10 m^-3

I am having issues with part c. I know I need to figure out how many electrons are leaving the wire per second and then from there it should be a straight division problem using the 6.022 x 10^23 for Avogradro's number.

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# Homework Help: Current and Avogadro's Number

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