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

What does 0 electric potential difference mean?

  1. Mar 28, 2014 #1
    This isn't a homework question, but while working on some questions in Physics AP C, i've come across several questions involving 0 PD (potential difference).
    My question is simple; what does 0 PD mean?
    so far i know that 0 potential difference of any kind is arbitrary, since it represents the amount of energy required to displace it from point a to b. Therefore i am aware that 0 does not really mean: 'no potential energy at that point'.

    Screen Shot 2014-03-28 at 11.09.25 PM.png
    (new to forum; i hope there's an image above this line^^)

    the image above is a simulation of 1 negative charge, and 3 positive charge with some distance between them. the white area supposedly shows 0 PD, but what is so special about it? Does a charge or an object behave differently in those areas?
  2. jcsd
  3. Mar 28, 2014 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    0 potential value is arbitrary; 0 potential difference is not.

    0 potential difference between two locations means that the potential values AT each point are the same.

    As to your specific question:
    What would be the effective force on a charged particle placed within the white region?
  4. Mar 28, 2014 #3


    User Avatar
    Gold Member

    As arildno stated, you're not being consistent with use of your termonology.
    [itex]U_{q}="Electric Potential"[/itex]
    [itex]V= "Potential Difference" = U_{q_{f}}-U_{q_{o}}[/itex]
    The second is what you measure with your ammeter in class.
  5. Mar 28, 2014 #4


    User Avatar
    Gold Member

    To actually answer your question, 0 electric potential is like setting a 0 for gravitational potential energy, put it where it's most convenient (probably ground in your circuit)
    0 Potential difference means that the 2 points your measuring between are at the same electric potential.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: What does 0 electric potential difference mean?