PURPOSE: To demonstrate the third law of motion.

DESCRIPTION: Two dynamics carts (either M and 2M or M and M) are placed  together on the track.  One cart is equipped with a compressed spring. Lightly tapping the release mechanism for the spring  releases the carts with no external force. Motion sensors can be used to  measure and plot the velocity vs time graph of each cart after release.  Additionally, the track can be balanced on a pivot to show the center of mass remains constant.

SUGGESTIONS:

REFERENCES:

EQUIPMENT: Dynamics track with two mass M and one mass 2M carts and computer with two motion sensors.

SETUP TIME: 10 min.

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