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fishturtle1
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Homework Statement
A 5.00-A current runs through a 12 gauge copper wire (diameter 2.05mm) and through a light bulb. Copper has 8.5 x 1028 free electrons per cubic meter.
c) At what see does a typical electron pass by any given point in the wire?
Homework Equations
J = nqvd
The Attempt at a Solution
The previous parts of the question I solved for current density.
J = 3.105 x 106 A / m2
n = 8.5 x 1028 electrons / m3
vd = J / n|q|
I substituted all my values in:
vd = (3.105 x 106 ) / (8.5 x 1028)(1.602 x 10-28)
vd = (3.105 x 106) / 13.167 m/s
vd = 2.28 x 105 m/s
the correct answer is vd = 0.111 mm/s
I'm sorry this is probably an arithmetic error but i can't see what I did wrong