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

compute the average time between collisions T for conduction electrons in copper.

2. Relevant equations

Vd=-e*E*T/(Me)

Where e is electron's charge

E is electric Field

T is what i'm solving for

And Me is mass of the electron

Vd=I/PA

3. The attempt at a solution

so it was given that a copper wire with a 1.0mm diameter had a current of 1A...and it's mass density is 8900kg/m^3.

So m= 1 electron(8900kg/m^3)(6.02X10^23 atoms/0.0635kg) = 8.4 X 10^28/m^3

So

Vd=1A/(8.4X10^28 m^-3)(1.6X10^-19C)(7.9x10^-7m^2) = 9.4 x 10^-5 m/s

So now...

Vd=-e*E*T/(Me)

So T=(Vd)(Me)/(-e)(E)

I have Vd, Me is mass of the electron, and -e is charge of the electron. I need the electric force...and am stumped. How do I get it from the given info? Thanks for the help.

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# Homework Help: Time between collisions

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