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

Calculate how many conduction electrons pass through a given area per second when a current of 1A flows.

2. Relevant equations

Current density, j = i/A (i=current, A=cross sectional area)

Current desntiy, j = nevD (n=no of electrons per unit volume, e=charge on electron, vD=drift velocity)

3. The attempt at a solution

I've taken an element of volume of length vDt and cross-sect area, A. I've surmised then that the total number of electrons in that area will beN=nAvDt.

All of those electrons will then cross a plane in 1 second, so i've equated j=i/A=nevD, and substituted n from the earlier (bold) equation - n=N/AvD. However, that produces a result of N=i/e=1/e ... doesn't look right! Help!!

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# Homework Help: Number of conduction electrons question

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