Plate Sliding Under a Soda Can
A can is placed on top of a metal sheet on a stool. A broom hits the sheet causing it to fly from underneath the can, while the can remains stationary. The impulse of the net force is made very small by reducing the time over which the metal sheet acts on the can. In other words, the force of the sheet does not act on the can long enough to accelerate it, so it does not move.