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!

Relative and absolute potential?

  1. Aug 7, 2012 #1
    Hello.
    I've been thinking about potential on charged capacitors, and got confused.

    A charge is AFAIK absolute - there is a balance of electrons and protons in matter, which can be biased one way or another.
    However, voltage is defined as difference of potential, not an absolute value.
    So, 100 volts on the ground is the same as 100V in a middle of a charged thundercloud.

    But what kind of charge distribution could there be on a charged capacitor?

    The experiment is such:
    Take 3 100000V capacitors, and stack them in series.
    When charged, top one would have 200kV on one side and 300kV on the other.
    These voltages alone are sufficient to produce electric field-related effects, like static cling.

    What would happen when that upper capacitor is disconnected from the rest?
    Would it maintain the absolute charges - i.e. would there be a 300kV and 200kV worth of static cling?
    It would obviously maintain a 100kV difference between the poles, but would the absolute offset remain - that is, is there any difference between it and the lower capacitor in the stack that have 0V and 100kV?
     
  2. jcsd
  3. Aug 7, 2012 #2

    Simon Bridge

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    No. There's not.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Relative and absolute potential?
Loading...