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

A glass tube with a cross-sectional area of 8^-2 m^2 contains an ionizd gas. The densities are 10^15 positive ions/m^3 and 10^11 free electrons/m3. Under the influence of an applied voltage, the postive ions are moving with an average axial velocity of 6 x 10^3 m/s. At that same point the axial velocity of the electrons is 1000 times as great. Calculate the electric current moving through.

2. Relevant equations

A= c/s = dq(+ ions)/dt + dq(- ions)

e = 1.6602E-19

3. The attempt at a solution

10^15*6x10^3*.08=4.8e17

4.8e17 * 1.602x10^-19 = .0769c/s

10^11*6x10^6*.08

4.8e16 * 1.602x10^-19 = .00769c/s

.00769+.0769= .0845c/s = 84.5mA

This isn't correct, but i don't know why? please help.

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# Homework Help: Calculating current

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