Changes

Force is defined as rate of change of [[momentum]] of a body . F = dp/dt. For non-[[Theory of Relativity|relativistic]] speeds, the momentum is given by ''p = m v'', giving ''F = m a''.<ref>Marcelo Alonso and Edward J. Finn, ''Fundamental University Physics'', Addison-Wesley.</ref> In these expressions, ''F'' stands for the total vector sum of all forces, ''m'' for the mass of the object, ''a'' for its [[acceleration]] expressed as a vector, ''p'' stands for momentum vector  and ''v'' for velocity vector. The expression ''F = m a'' is Newton's Second Law, which was stated first by Sir [[Isaac Newton]].  

Force is defined as rate of change of [[momentum]] of a body (F = dp/dt). Unit of force is [[newton]].

 

For non-[[Theory of Relativity|relativistic]] speeds, the momentum is given by ''p = m v'', giving ''F = m a''.<ref>Marcelo Alonso and Edward J. Finn, ''Fundamental University Physics'', Addison-Wesley.</ref> In these expressions, ''F'' stands for the total vector sum of all forces, ''m'' for the mass of the object, ''a'' for its [[acceleration]] expressed as a vector, ''p'' stands for momentum vector  and ''v'' for velocity vector. The expression ''F = m a'' is Newton's Second Law, which was stated first by Sir [[Isaac Newton]].