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!

Homework Help: Electric potential problem

  1. Aug 21, 2016 #1
    1. The problem statement, all variables and given/known data
    In the figure, a metal sphere with charge q=https://edugen.wileyplus.com/edugen/shared/assignment/test/session.quest2561214entrance1_N10031.mml?size=14&ver=1471825532267&algorithm=1&rnd=1471825539091 [Broken] μC and radius r=https://edugen.wileyplus.com/edugen/shared/assignment/test/session.quest2561214entrance1_N1003F.mml?size=14&ver=1471825532267&algorithm=1&rnd=1471825539091 [Broken] cm is concentric with a larger metal sphere with charge Q=https://edugen.wileyplus.com/edugen/shared/assignment/test/session.quest2561214entrance1_N1004D.mml?size=14&ver=1471825532267&algorithm=1&rnd=1471825539091 [Broken] μC and radius R=https://edugen.wileyplus.com/edugen/shared/assignment/test/session.quest2561214entrance1_N1005B.mml?size=14&ver=1471825532267&algorithm=1&rnd=1471825539091 [Broken]cm. (a) What is the magnitude of the potential difference between the spheres? If we connect the spheres with a wire, what then is the charge on (b) the smaller sphere and (c) the larger sphere?

    2. Relevant equations

    3. The attempt at a solution
    I got b and c correct, it is just part a that I am confused. The question ask for the potential difference between the two sphere, so i simply took the difference. ΔV=k*(Q/R - q/r)=7.8E5, please help me understand why this is not the correct answer. Thanks

    Attached Files:

    Last edited by a moderator: May 8, 2017
  2. jcsd
  3. Aug 21, 2016 #2

    Paul Colby

    User Avatar
    Gold Member

    The potential change (difference) is the work it takes to move a unit of charge from one point to another. How would you calculate that work?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted