
 Newton's Equation of Motion (Site not responding. Last check: 20071102) 
  That this equation is really a second order differential equation in time, t, can be understood from the fact that acceleration is the derivative of the velocity, v, to time and velocity is the derivative of position, u, to time, viz. 
  To find this solution in the case that an analytical solution is difficult, one can solve the second order differential equation in a numerical fashion by numerical integration. 
  Thus armed with these two values and the equation of motion, one may numerically determine the trajectory of particles. 
 chemistry.clemson.edu /ChemDocs/marcusgroup/software/CONCEPT/QMA/FMA/FMA.HTM (524 words) 
