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

A 150 km long high-voltage transmission line 2.0 cm in diameter carries a steady current of 1030 A. If the conductor is copper with a free charge density of 8.9 1028 electrons per cubic meter, how many years does it take one electron to travel the full length of the cable?

2. Relevant equations

I= nq(vd)A

where A is the area

vd is the drift speed

n is the charge density

and I is the current

3. The attempt at a solution

SO we are solving for the drift speed so i thought this equation would work. i found the area first using surface area of a cylinder 2pir^2+2pirh and i got 18840.0025 because i converted cm and km both to m.

then i plugged everything else in and the answer was wrong

:(

oh yea and i used -1 for the q which is the charge. i assumed -1 b/c they are electrons

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# Homework Help: Drift speed on copper cable

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