The law of conservation of momentum can be applied to a wide range of processes whether it is the collision of subatomic particles, rocket propulsion, or the recoil of a cannon. In this experiment two technologies, the Arduino microcontroller and a PASCO smart cart, are used to create a movable rubber band launcher. The Arduino microcontroller is programmed to turn a servo motor through switch activation to release the rubber band. While the rubber band moves in one direction, the cart recoils and moves in the opposite direction, all being a consequence of the conservation of momentum. A suitable analysis of the experimental data produces values for the initial kinetic energy of the launched rubber band and the energy transferred by the system.

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