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!

Energy between objects

  1. Nov 15, 2009 #1
    1. The problem statement, all variables and given/known data
    Two 0.54-k basketballs, each with a radius of 16 cm, are just touching.
    A. How much energy is required to change the separation between the centers of the basketballs to 1.0 m?
    B. How much energy is required to change the separation between the centers of the basketballs to 14 m?


    2. Relevant equations
    Im not sure what to use, but its probably obvious


    3. The attempt at a solution
    None, i dont know where to start
     
  2. jcsd
  3. Nov 16, 2009 #2
    this smells like a universal gravitational potential problem (assuming these balls are not on the surface of the earth), so what is your potential equation?
     
  4. Nov 16, 2009 #3
    okay, F=G(m1)(m2)/r^2 but if the raduis of the balls are .16 m, do i use that as the radius, or do i double it beause the balls are the same size?
     
  5. Nov 16, 2009 #4
    (ignoring the detail with the radius) your expression solves for the force one ball exerts on another. Once you solve for this force, what good is it?
     
  6. Nov 16, 2009 #5
    im kind of confused, am i using the right equation?
     
  7. Nov 16, 2009 #6
    no, use this equation.

    [tex]U=G\frac{m_1m_2}{D}[/tex]

    where:
    U= potential energy
    G= newton's gravity constant
    D= distance from either respective centers
     
  8. Nov 16, 2009 #7
    so it should look like this F=(6.67E-11)(.54)(.54)/.16 ?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Energy between objects
Loading...