PURPOSE: To demonstrate F = ma.
DESCRIPTION: A small mass hanging over a frictionless pulley provides the constant force which accelerates the glider between gates A and B. Using the photogate timing system, the time for the glider to travel from A to B can be measured, or the velocities of the glider at positions A and B can be measured using the 5 cm tab mounted on the glider. The accelerating force can be varied by adding additional masses, or gliders of mass M, 2M, and 3M (2M + M) can be used. A careful measurement yields a result good to a few percent.
REFERENCES: (PIRA 1G10.10) See instruction sheet for Photocell Gate Timer in Demonstration Reference File.
EQUIPMENT: Air track, photocell gate timer system, gliders of mass M and 2M, small masses with audiotape frictionless cord, as photographed.
SETUP TIME: 5 min.
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