Public School, Deer Creek Minnesota, 1918 LakesnWoods.com Postcard and Postcard Image Collection - click image to enlarge Aerial view, Deer Creek Minnesota, 1972
Whenever work is done upon an object by an external force, there will be a change in the total mechanical energy of the object. If only internal forces are doing work (no work done by external forces), there is no change in total mechanical energy; the total mechanical energy is said to be conserved.
â¢Motion is the change of position over time. â¢A force is a push or a pull and can cause an object to change its speed or direction. â¢When you see a change in an objects motion, one or more forces caused the change. When it changes its position relative point. Motion is a change in position over time.