Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Finding Force From Potential Energy

  1. Nov 19, 2011 #1
    1. The problem statement, all variables and given/known data
    The potential energy of two neutral molecules may be modelled using the Lennard Jones potential,
    [tex]U(x)=U_0(\frac{\sigma^{12}}{x^{12}} - \frac{\sigma^6}{x^6})[/tex]
    where [itex]U_0[/itex] and [itex]\sigma[/itex] are positive constants and [itex]x[/itex] is the distance between the two molecules.

    a) Find the force at an arbitrary point x ?

    2. Relevant equations

    conservative forces and potential energy

    3. The attempt at a solution
    [tex]F(x) = -\frac{dU}{dx}= U_0(12\frac{\sigma^{12}}{x^{13}} - 6\frac{\sigma^6}{x^7})[/tex]

    Is my answer correct ?
  2. jcsd
  3. Nov 19, 2011 #2


    User Avatar

    Staff: Mentor

    Looks fine.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook