Need a little help on Kinematics. Say for instance, an object was dropped by a steadily rising body. To determine the velocity of the falling object after a certain time would be V(f)=(-9.81)(t). But if one were to find the distance between the falling object and the rising body, how could you do it? I tried by finding the change in displacement (delta x=(1/2)(-9.81)(t)^2) and added (t)(m/s rate of rising body). I've been told this is incorrect. If incorrect, how can i approach any problems like that in the future?