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!

Two repelling spheres

  1. Jul 15, 2012 #1
    Solved.
     
    Last edited: Jul 15, 2012
  2. jcsd
  3. Jul 15, 2012 #2

    TSny

    User Avatar
    Homework Helper
    Gold Member

    Electrostatic forces obey Newton's third law. Based on this, fill in the blank:

    Suppose Q = 2q. If Q exerts an electrical force of 2.0 N on q, then q exerts an electrical force of ______ N on Q.
     
  4. Jul 15, 2012 #3
    2q because the forces must be equal. Doesn't this agree with my answers?

    Or does it mean that the charges can be anything as long as the force remains constant, in which case the answers would be:

    True
    False
    True
    True
    True
     
  5. Jul 15, 2012 #4

    TSny

    User Avatar
    Homework Helper
    Gold Member

    One of your answers is still wrong. Hint: If the electrical forces are equal, then how can X hang at the smaller angle?
     
  6. Jul 15, 2012 #5
    It must have a greater mass, so the mass one is false.

    Thank you so much!
     
  7. Jul 26, 2012 #6

    berkeman

    User Avatar

    Staff: Mentor

    It is against the PF rules to deleted your posts after you have received help. Check your PMs.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook