Deriving F = ma


BHS -> Mr. Stanbrough -> Physics -> Mechanics -> Momentum -> The "Real" 2nd Law -> this page

If the net force on an object equals the rate of change of its momentum, then:

Actually, the rate of change of momentum is the derivative of the momentum with respect to time, and calculus is required to manipulate the equation:

Deriving f = ma

Here, since both m and v are variable quantities, their derivative must be treated as the derivative of a product. The quantity dv/dt is the rate the object's velocity changes, which is its acceleration. The quantity dm/dt is the rate that the object's mass changes.

last update April 10, 2000 by JL Stanbrough