# Free fall Experiment Help

by bilalbajwa
Tags: experiment, fall, free
 P: 560 I think you are getting there and probably understand. But anyways, the AVERAGE velocity of an object over a specific time interval (under constant acceleration) is $$v_{ave}=\frac{v_{i}+v_{f}}{2}$$ Since Vi is 0 in your the case of your object, you could express $$v_{ave}=\frac{v_{f}}{2}$$ Another way of expressing $$v_{ave}$$ is $$v_{ave}=\frac{\Delta d}{\Delta t}$$ Where delta d is the change in displacement and delta t is the change in time So this is where the yi/ti comes from, its simply the average velocity. I feel that I am not doing a very good job of explaining this.. :/