[lammps-users] Derivative of the kinetic energy

Dear all,

I have a question but it may not be about the LAMMPS exactly.
We know that d/dt( 0.5 m Vi^2 ) is equal to Fi.Vi for each particle where
Fi is the force vector on atom i and Vi is its velocity vector.
When I compute the d/dt( 0.5 m Vi^2) numerically using the finite
difference method with a very small time step, I see it is not equal to
Fi.Vi . Is it for using finite difference method?
I am really confused. Any help would be appreciated.

Ali Rajabpour

Try Fi = rate of change of momentum ... i.e. Fi = d/dt(m vi) rather
than rate of change of kinetic energy ...


2008/10/6 Ali Rajabpour <[email protected]>: