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.
If the forces on an object are not balanced then it could do one of a number of things - 1. change speed (accelerate or decelerate) 2. change direction 3. â¦ change shape 4. spin if the forces on an object are balanced then it will stay in its original direction at a steady speed (this could be zero ie stationary)