Resistivity and Ohm's Law question

AI Thread Summary
The discussion revolves around calculating the resistance of a wire connected to a 12V battery with 6.4 x 10^19 electrons passing through it each second. The initial calculations mistakenly used the mass of an electron instead of its charge, leading to incorrect resistance values. The correct charge of an electron is approximately 1.6 x 10^-19 Coulombs, which is crucial for accurate calculations. After correcting the error, the resistance is determined to be 1.2Ω. The thread highlights the importance of using the correct constants in physics calculations.
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Homework Statement


A long wire connected to the terminals of a 12V battery has 6.4 x 1019 electrons passing a cross section of wire each second. calculate it's resistance.

answer is 1.2Ω

Homework Equations


q = ne
q = IE
R=ρ L/A

The Attempt at a Solution


V= 12v
n= 6.4 x 1019 electrons
R=?

First I used the number of electrons to find my charge (q)
q = ne
q = (6.4 x 1019) ( 9 x 10-31)
q = 5.76 x 10 -11

Then calculating my current
I= Q/T
Im assuming T is 1s, because it says "passing a cross section of wire each second"
I = 5.76 x 10 -11/ 1
I= 5.76 x 10 -11

Then i calculated my resistance
R= V/R
R= 12/5.76 x 10 -11
R= 2.0 x 1011

What am i doing wrong? D:
 
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The charge of an electron is e=1.6(10-19) C.
 
q = ne
q = (6.4 x 1019) ( 9 x 10-31[/color])
... that would be the electron mass.

e=1.60217646×10-19 Coulombs
 
rock.freak667 said:
The charge of an electron is e=1.6(10-19) C.

Simon Bridge said:
... that would be the electron mass.

e=1.60217646×10-19 Coulombs

LOL! CRAP! i knew that~ :) Thank you :3 I was going insane for a bit.
 
Happens to the best of us :-)
 
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