Could some people help to solve an arguement??? A question came up on the GameDev forums about a diagram with a force being applied to it. I provide the link, but be warned, there is 6 pages of posts to go through, although some are quite funny, quite a heated battle ensues: http://www.gamedev.net/community/forums/topic.asp?topic_id=352000 At first I was messing about with the people posting, but they then settled on a solution of f=F for the diagram; the resulting force at the center of mass would be the same as the input force. I then stopped joking and provided a solution of f=F-e, where e is the force lost (for various reason detailed in the above link). The main basis of my arguement is the conservation of Energy and that for f=F to be true it would need to defy that law. Also, as an arguement to real world applications the basic principles of elastic and in-elastic collisions would also prohibit f=F. Could the good people of the physics forums help resolve this? Who is correct?