PURPOSE: To determine the speed of an air gun pellet using conservation of momentum in an inelastic collision.
DESCRIPTION: The pellet is shot into a receptacle mounted on an air track glider. Conservation of momentum in the ensuing totally inelastic collision allows determination of the velocity v with which the pellet was shot: v = [(M+m)/m] V, where m is the mass of the pellet, M is the mass of the glider/receptacle, and V is the measured velocity with which the glider leaves the collision. The speed of the glider is determined using a photocell gate timer. Compare this result with the result from the standard ballistic pendulum demonstration using the air gun pellet, Demonstration C7-51.
For adequate repeatability, pump the gun eight times. Be familiar with the safety mechanism, and know where the pellet exits the gun before firing.
SUGGESTIONS: BE CAREFUL WITH GUN!!!
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Pellet gun with pellets, glider with receptacle, air track, and photocell gate timer.
SETUP TIME: 5 min.
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