Guys...im just a high school student and im presented with a ' challenge ' by my physics teacher. I really hope to solve this by myself...but i hope you guys can give me tips on solving this problem..thnx Imagine a big box on a surface with friction = 0 and a smaller object is thrown on top of with with a force denoted F. Can we calculate when will the smaller object move in phase with the bigger object? with regard with the distance travelled by the big box. ( in the sense that the smaller object stops moving??) Thnx alot. I mean that if there is a given velocity and everything is given, is there a way to find out how much distance the big box has moved when the small object on it stopped moving? Is there any other simpler ways to solve it in terms of kinematics?