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!

Electrostatics Problem

  1. Feb 26, 2005 #1
    I am having trouble with this problem
    There is a sphere haveing nonuniform volume charge desnity p=ar where a is constant and r is radial distance from centre of sphere.
    Radius of sphere is R
    we have to find electric field at centre of sphere.
  2. jcsd
  3. Feb 26, 2005 #2


    User Avatar
    Staff Emeritus
    Science Advisor

    Okay, what have you done?

    The standard way of determining the electric field due to a distribution of charge is set up the expression for the force due to an infinitesmal volume of the charge and then integrate of the body.

    In this case, while the distribution of charge is not uniform it is spherically symmetric and since you are asked for the field strength at the center of the sphere, you don't really need to do the integration! Imagine two infinitesmal volume on opposite sides of the sphere and equally distant from the center. What can you say about the total force on a test charge at the center from those two volumes?
    Last edited: Feb 26, 2005
  4. Feb 27, 2005 #3
    I understood a bit of your suggestion but i am unable to put it to use to solve my problem
    i know for a sphere with uniform charge denisity electric field is zero at centre but for non uniform it beats me.
    i first thought about doing it by dividing sphere into think spherical shells then integrating but then i remembered that you cannot integrate as such as electric field due to thin spherical shell at centre is zero

    can someone please help me.
    Last edited: Feb 27, 2005
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Electrostatics Problem
  1. Electrostatics problem (Replies: 1)

  2. Electrostatics problem (Replies: 2)

  3. Electrostatic problem (Replies: 4)

  4. Electrostatics problem (Replies: 2)

  5. Electrostatics Problem (Replies: 5)