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

A 1.0-mm-diameter wire has 1000 excess electrons per centimeter of length. What is the surface charge density?

2. Relevant equations

[tex]\eta[/tex] = Q/A

3. The attempt at a solution

[tex]\eta[/tex] = (100000 * 1.6*10^-19)/([tex]\pi[/tex] * (5*10^-4)2)

But that gets me 2.037 * 10^-8 C/m^2

The answer is 5.1 * 10^-12 C/m^2

Any ideas?

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# Homework Help: Finding the surface charge density

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