Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Is the book wrong again for this e field problem?

  1. Sep 6, 2011 #1
    1. The problem statement, all variables and given/known data

    A nonconducting SPHERICAL SHELL of inner radius R1 and outer radius R2 has a uniform volume charge density p. Find the total charge on the shell

    2. Relevant equations
    Q=pV=p(4/3)*pi*(R2^3-R1^3) << That's what I got
    the book had Q=pV=p(4/3)*pi*(r^3-R1^3) <<how can that be correct if you're finding the total charge the shell, not from R1 to r?
     
  2. jcsd
  3. Sep 6, 2011 #2
    Your answer is right, but are you sure that you are quoting the book correctly? The book could be referring to the charge contained within a radius r, such that R1<r<R2 (which can be applied to find the electric field by Gauss' law)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook