The speed of the electrons in the conductor

gabor7896
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Homework Statement


A copper conductor with a cross-section of A and a length of is connected to a battery with a electromotive force of U. The resistance of the conductor is R, and the internal resistance of the battery is negligible.
U = 220 V
l = 10 m
A = 10 mm2
R = 0.01695 \Omega
Determine the average speed of the electrons!


The Attempt at a Solution


I know the electric current. But I have no idea how many electrons are moving.




I'm not a native speaker. I may have grammer mistakes.
 
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I will give u all the equations u need(i think) and try to solve it by urself

I=dQ/dt
dQ=nqvAdt thus I=nqvA n is the charge concentration, v the electrons velocity, A surface area

J=I/A J is the current's density

v=J/nq

hope i helped
 
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