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!

Potential difference across capacitor

  1. May 9, 2017 #1
    • Member advised to use the homework template for posts in the homework sections of PF.
    Hi, the solution of my exercise says that the potential difference in the capacitor C1 is zero. 1494361264-screenshot-from-2017-05-09-16-06-36.png
    Can you please explain me why it's the case ?

    Thank you.
  2. jcsd
  3. May 9, 2017 #2


    User Avatar
    Homework Helper
    Gold Member

    You don't have any values for those capacitors. This is an example of a bridge circuit. Read this article for some insight. https://en.wikipedia.org/wiki/Bridge_circuit

    Resistors and capacitors work differently, but be assured that there are capacitor values which would result in the voltage at the top of the C1 to be the same voltage as the bottom of C1. For example, if we have 10.5 volts at the top and 10.5 volts at the bottom, then 10.5-10.5 = 0.
  4. May 9, 2017 #3
    Owwww I'm sorry, I forgot to give the values !!

    In fact, we have C2=C4 = 1.0μF and C3=C5 = 2.0μF.
  5. May 9, 2017 #4
    However what if, in this case, we have C2 =/= C4 OR C3 =/=C5, C1 wouldn't be equal to zero anymore, right ?
  6. May 9, 2017 #5


    User Avatar

    Staff: Mentor

  7. May 9, 2017 #6


    User Avatar
    Homework Helper
    Gold Member

    You should really take a look at the article on Bridge circuits, which I pointed to in the earlier post. Once you understand how resistor bridge circuits work, it will not be much of a stretch to understand other components, such as capacitors.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted