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!

Magnitude of the work done by electric field.

  1. Feb 14, 2017 #1
    1. The problem statement, all variables and given/known data
    The membrane around a cell normally has layers of charge that create a potential difference between its outer and inner surfaces. This difference is about 72 mV .

    When a singly ionized potassium ion moves through a channel in the membrane passing from the outside to the inside, what is the magnitude of the work done by the electric field of the membrane?

    upload_2017-2-14_18-16-7.png

    2. Relevant equations
    W = F*d
    W = V*U

    3. The attempt at a solution
    So I know that the charge of a K ion is +1 so it is simply 1.6e-19 and converting 72 mV to 0.072 V I can then just multiply both to get the change in work correct? I don't get why that is wrong then.
     
  2. jcsd
  3. Feb 14, 2017 #2

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    Just a multiplication error.
    Quick check: If you multiply 1.6*10-19 by 0.072, the result should be smaller than 10-19.
     
  4. Feb 14, 2017 #3
    Yeah I keep getting 1.15e-19. Isn't that correct, I cant seem to get a different answer on my calculator. Nevermind I got the answer. I was using -18 instead of -19.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Magnitude of the work done by electric field.
Loading...