1. The problem statement, all variables and given/known data It is possible to calculate the velocity of falling bodies (ignoring air resistance of course) using a gravitational acceleration constant. Assume: You don't know what the resistance is. The object started at rest. You DO know there is downwards motion. You don't know what the mass is. I am trying to get at an ending velocity for about 3-10 meters of accleration if that helps. Using that ending velocity, I can then easily calculate kinetic energy. If there is some other resistance, other than air, is it reasonable to simply reduce the acceleration by some amount to account for that resistance, if one is trying to get at a reasonable range for kinetic energy (in terms of the objects mass)? 2. Relevant equations body at rest accleration and ending velocity: v^2=2ad ke=1/2mv^2 3. The attempt at a solution This really simply requires a "reality" check to see if I am conceptually on track. I may have some follow questions depending on how things work out, if y'all don't mind. I am trying to make sure that my concepts of physics are straight, so I can explain some of these concepts to a couple of people who know much less than I do.