The reason why I am suspecting the solution is wrong is because the final step is dividing something with units of electrons/min by something with units of electrons/meter. Am I right about the solution being wrong? If I am wrong, then what am I not seeing? If I am right that the book is wrong, then what is the correct final answer and what must I correct in my book's solution?(adsbygoogle = window.adsbygoogle || []).push({});

The question is:

"An AWG#12 copper wire, a size in common use in residential wiring, contains approximately 2.77 x 10^23 free electrons per meter length, assuming one free conduction electron per atom. What percentage of these electrons will pass a fixed cross section if the conductor carries a constantcurrent of 25.0 A?"

The solution is:

"(25.0 C/s)/(1.602 x 10^(-19) C/electron) = 1.56 x 10^20 electron/s

(1.56 x 10^20 electron/s)(60s/min) = 9.36 x 10^21 electrons/min

(9.36 x 10^21)/(2.77 x 10^23)(100%) = 3.38%"

Any input would be greatly appreciated!

Thanks in advance!

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Simple beginner question in Electric Circuits Course (Is the solution wrong?)

**Physics Forums | Science Articles, Homework Help, Discussion**