This apparatus demonstrates onedimensional collisions and verifies the law of conservation of momentum using two objects of equal mass and size. When the two objects collide along the same straight line and the system is from external forces, the total momentum before and after the collision remains constant. The design makes this principle clear and repeatable for teaching, lab verification, and handson learning. Key benefits Teaches a fundamental physics principle in a direct, observable way. Students and instructors can see momentum conservation during collisions along a single axis. Simplifies setup and measurement for onedimensional collision experiments. The equalmass, equalsize objects produce clear, comparable results. Supports repeatable and reliable demonstrations. The controlled collision along a straight line reduces variables and makes experiment outcomes easier to analyze. Main functions and attributes Function: Demonstrates elastic and inelastic onedimensional collisions and verifies momentum conservation in an isolated system. Mass and size: Uses two objects matched in mass and size to ensure symmetric collision behavior and straightforward data interpretation. Motion: Collisions and postcollision motion occur along the same straight line for clear, onedimensional analysis. Design quality: Constructed for repeated use in classroom and lab settings, providing consistent collision behavior and performance suitable for instructional use. Compatibility and performance Compatible with classroom equipment and basic lab measurement tools such as motion sensors, timers, and video analysis systems. Performance supports accurate verification of momentum conservation when external forces are minimized or controlled. Works well with standard physics curricula and laboratory protocols for mechanics and collision experiments. Practical use scenarios school physics lab: Demonstrate conservation of momentum during a guided classroom experiment. Students can measure velocities before and after collision and compare total momentum. University undergraduate mechanics lab: Use for quantitative verification of momentum conservation, data collection, and analysis in experiment reports. Student projects and demonstrations: Provide a handson activity for science fairs or outreach events to illustrate core mechanics concepts. Why this product solves teaching and verification needs Provides a focused, onedimensional collision setup that reduces experimental complexity and emphasizes the momentum principle. Matching masses and sizes minimize confounding variables, making data interpretation more straightforward. Enables instructors and students to conduct repeatable experiments and collect clear evidence of momentum conservation. This apparatus is a practical, reliable tool for demonstrating onedimensional collisions and verifying the law of conservation of momentum in educational and laboratory settings.