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!

Point charges and potential

  1. Feb 14, 2005 #1
    Three point charges are arranged at the corners of a square of side L. What is the potential at the fourth corner (point A), taking V = 0 at a great distance?

    OK, I am very confused. First of all, Giancoli (my textbook) seems to explain how to do this for one point charge, but I am confused about doing this for three charges. Second, what do they mean by "at a great distance"? I am assuming I would want to use V = 1/4piE0 Q/r. So I am guessing that I would have to do some kind of vector deal? Help appreciated. :redface:
  2. jcsd
  3. Feb 14, 2005 #2
    Um never mind. So I thought about this again and decided to use V=kQ/L for each point individually -- does that make sense? And then add them up to get V total. So I wound up with ((1/square root 2) +1) x kQ/L. My book says the answer is square root 2 x k x Q/2L (square root 2 + 1). I believe this is the same thing?
  4. Feb 14, 2005 #3


    User Avatar
    Science Advisor
    Homework Helper

    That "taking V = 0 at a great distance" means that an infinity the potential is 0,which means that the potential is actually negative.So you'd have to add 3 negative #-s,that's all.

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Point charges and potential