1. Not finding help here? Sign up for a free 30min 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!

Electric force between objects that are in brief contact

  1. Mar 25, 2013 #1
    1. The problem statement, all variables and given/known data

    Two small charged objects of the same mass and volume are brought into brief contact with each other. If the initial charges on the two objects are -3.00 x10^-6 and -1.50 x10^-6, what is the electric force between the objects when they are seperated to a distance of 0.500m after contact?

    The answer is 1.82 x10^1 N

    2. Relevant equations

    F=KQ1Q2/r^2


    3. The attempt at a solution

    I thought it is just plug in the numbers but i get a different answer. So is there anything that goes on when they are in contact?

    F= (9.0x10^9)(-3.00x10^-6)(-1.50x10^-6)/(0.500)^2
    =0.162N
     
  2. jcsd
  3. Mar 25, 2013 #2
    The important thing here is that they are brought into contact first.
    What changes does that cause?
     
  4. Mar 25, 2013 #3
    im not really sure...

    umm their initial distance? Or it will have to be something to do with their charge (transfer of electro maybe)?
     
  5. Mar 25, 2013 #4
    I think the objects you have are conductors?? What happens in this case?? And anyway are you sure the result is not 1.82x10^(-1)?? (you put 10^1)...
     
  6. Mar 25, 2013 #5
    I think you have to assume they're conductors, since it gives the right answer :)

    Yes - this is the answer I got.

    Jabababa - When you put two unequally charged conductors in contact, what happens to the charges on them?
     
  7. Mar 25, 2013 #6
    Just as I thought :smile:
     
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: Electric force between objects that are in brief contact
Loading...