1. Limited time only! Sign up for a free 30min personal 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!

Electric field in a hollow cylinder

  1. Oct 29, 2011 #1
    An infinitely long thick hollow cylinder has inner radius Rin and outer radius Rout. It has a non-uniform volume charge density, ρ(r) = ρ0r/Rout where r is the distance from the cylinder axis. What is the electric field magnitude as a function of r, for Rin < r < Rout?

    for this problem, when you find qinside, do you integrate from Rin to r or from Rin to Rout? i'm confused because i would have expected it to be the latter, but in the solutions they integrate from Rin to r. can someone please explain this?

    also, if you try to find the e-field where r > Rout, do you integrate from r to Rout?

    Solution is here (problem II):
    http://www.physics.gatech.edu/~em92/Classes/Fall2011/2212GHJ/main/quiz_help/200908/q2s.pdf
     
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Oct 30, 2011 #2

    rude man

    User Avatar
    Homework Helper
    Gold Member

    Just use Gauss' theorem. The surface has radius r, and
    q(inside) is whatever's inside!
     
  4. Oct 30, 2011 #3
    since in the example in the document it asks for Rin < r < Rout.. why does it integrate from Rout to r??
     
  5. Oct 30, 2011 #4

    rude man

    User Avatar
    Homework Helper
    Gold Member

    It doesn't. It integrates from Rin to r.
     
  6. Oct 30, 2011 #5
    but why not Rin to Rout?
     
  7. Oct 30, 2011 #6

    rude man

    User Avatar
    Homework Helper
    Gold Member

    Because ity asks for the field at Rin < r < Rout, not AT Rout.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Electric field in a hollow cylinder
Loading...