The Newton Third Law of Motion Apparatus is a practical physics laboratory model designed to demonstrate Newton’s laws of motion, conservation of momentum, and one-dimensional elastic and inelastic collisions. It provides a clear hands-on setup for observing action and reaction forces between moving bodies.The apparatus comprises a pair of identical wooden trolleys, each mounted on three wheels to minimize friction during motion. Each trolley is fitted with a spring-loaded rod that provides impulse when released. Slots are provided for different levels of spring compression, allowing variation in stored energy and impact force.

A trigger knob is fitted on top of each trolley to activate the spring mechanism. This apparatus is useful for demonstrating collision behavior, recoil motion, momentum transfer, and action-reaction principles in school, college, and university physics laboratories.

Experimental Objectives

To demonstrate Newton’s Third Law of Motion.
To study action and reaction forces between two trolleys.
To verify the principle of conservation of momentum.
To demonstrate elastic and inelastic collisions in one dimension.
To observe the effect of different spring compression levels on trolley motion.