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!

Homework Help: Electric charge, simple problem for most of you.

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

    A) Two electric charges each with the charge of -35 nC is 0.70m apart from each other. With how big of a force do they impact each other?

    B) A small metallic ball has a positive charge of 25nC. A particle with the charge +2.0nC is affected by a repellent force that's caused of the metallic ball. At what distance is the force of the ball 60 µN.

    2. Relevant equations

    3. The attempt at a solution

    I'd really love some clues or perhaps links to equations that are relevant to these types of problems. I've a hard time imagining that these problems are hard once you know the relevant equations since this is the most basic physics there is.
  2. jcsd
  3. Sep 1, 2013 #2
    Google coulomb's law.
  4. Sep 1, 2013 #3
  5. Sep 1, 2013 #4
    Thank you very much!
  6. Sep 25, 2013 #5
    Is this correct? F = q1*q2 / r^2 = -35*-35/0.49 = 2500?

    And if so, what is the power measured in?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted