1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Average Electron Drift Distance with AC Current

  1. Sep 14, 2015 #1
    1. The problem statement, all variables and given/known data
    A metal wire with 1023 free electrons per cubic centimeter is carrying 60 Hz alternating current with a maximum current density of 100 amps/cm2.
    a) Write an expression for the average electron drift velocity as a function of time (vd as a function of time).
    b) What is the average drift distance of free electrons in one direction in a half-cycle of current?

    2. Relevant equations
    J = σE = σEsin(ωt)
    ω = 2πν
    J = -eNevd

    3. The attempt at a solution
    Part a:

    J = -eNevd
    -eNevd = σEsin(ωt)
    vd = (-σEsin(ωt)) / (eNe)

    Part b:

    Need help here, I attempted to plug in ω = 2πν into the equation J = σEsin(ωt), but don't seem to be getting anywhere, because I don't have σ or E.
     
    Last edited: Sep 14, 2015
  2. jcsd
  3. Sep 14, 2015 #2

    Hesch

    User Avatar
    Gold Member

    Calculate the average absolute current density ( [ A/cm2 ] ).

    Calculate the amount of coulombs moved per second.

    Calculate the amount of centimeter wire-electrons is moved per second.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Average Electron Drift Distance with AC Current
Loading...