PhySP18SS5.4.28 So what does this have to do with the force of lift on a fast moving car? Okay, I’ll give you the simplified non mathematical version of this. This really requires a lot of statistics and Calculus. So I will give you the Reader’s Digest version: All this brownian motion of air molecules (O2 and N2 molecules) cause a standard air pressure (Force per unit area) of 14.7 psi (lbs per square in). This air pressure is at sea level on earth. It tells you that the air molecules have reached maximum entropy and they are bouncing all over the place in all different directions causing little tiny force vectors in all directions.