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

Spherical capacitor energy problem

  1. Jul 19, 2004 #1
    Show that the energy associated with a conducting sphere of radius R and charge Q surrounded by a vacuum is

    U = k*Q^2 / (2R)

    :smile: thanks
    Last edited: Jul 19, 2004
  2. jcsd
  3. Jul 20, 2004 #2


    User Avatar

    Where are you having difficulty with the problem?
  4. Jul 20, 2004 #3


    User Avatar
    Homework Helper

    Consider how much work you would have to do to bring all of the charge together from an infinite separation. In other words, how much work does it take to contract an infinitely large sphere of charge Q down to a small sphere of radius R?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook