The title isn't exactly accurate in describing what I am after. There is a ball moving along the ground, it was given an initial impulse, and now it is moving following conservation of momentum, gravity, air-resistance, friction, etc... If I wanted to take the energy from that rolling ball with say a gun-shaped device, the ball stops rolling and that energy is in my gun now. How could that be possible in real life? Then the energy could be applied to other objects whether they are moving or not.