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: Millikan oil drop experiment potential difference

  1. Feb 23, 2010 #1
    1. The problem statement, all variables and given/known data
    in a Millikan oil drop experiment, a uniform electric filed of 1.92 x 10^5 N/C is maintained in a region between two plates seperated by 1.5 cm. Find the potential difference between the plates.

    2. Relevant equations
    mg = q x E

    3. The attempt at a solution
    in order to find the q and hence find the voltage/potential you need to have mass. there is no mass given. I assume once you have mass you get q and from there you can find voltage using k(q/r)
  2. jcsd
  3. Feb 23, 2010 #2
    To find V, the pd between the plates:
    In a uniform electric field between parallel plates, the field can be calculated from the potential gradient. You have the field strength given and you know the plate separation.
    Does this help?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook