# Calculating air drag

by bwong
Tags: drag
 Emeritus Sci Advisor PF Gold P: 5,533 The average velocity is easy. It's just the change in position divided by the change in time. You'll need to do this for both the horizontal and vertical components of the motion. You can deduce the final velocity as follows. In Calculus I you would have learned that the average value $f_{av}$ of a function $f$ is given as follows. $$f_{av}=\frac{1}{b-a}\int_a^bf(x)dx$$ Since you know $f_{av}$, as well as the integrand and the lower limit of integration, you can find the upper limit of integration (which in your case will be the final speed).