实验七 动量守恒定律的验证（Experiment seven verification of the law of conservation of momentum）.doc

实验七 动量守恒定律的验证（Experiment seven verification of the law of conservation of momentum） Experiment seven verification of the law of conservation of momentum Experimental purpose 1. verify the law of conservation of momentum. 2. further familiar with air cushion rail and universal computer counter. 3. observe the characteristics of elastic collision and inelastic collision by observation. Experimental instrument Air cushion guide, air source, vernier caliper, computer counter, gas source, physical balance, etc.. Experimental principle If a mechanical system is not subjected to external forces, or the vector sum of the external forces is zero. The total momentum of the system remains the same, and this is the law of conservation of momentum. In this experiment, the law of conservation of momentum is verified by the collision of two sliders on an air cushion guide. In the horizontal rail friction force between the slider and the guide rails, children ignored, two children at the time of the collision in the internal force of the slider is the interaction in the horizontal direction, the role of external force, so the impact of conservation of momentum. For example, M1 and M2 represent the mass of the two sliders, respectively. The velocities of the two sliders before and after collisions are expressed by V1, V2, and respectively, and the law of conservation of momentum can be obtained (71) The following are discussed separately: 1. perfectly elastic collision Elastic collision is characterized by momentum conservation before and after collision and mechanical energy conservation. If both ends in two children of the collision with the slider on the slider. The buffer spring, when touching, because the recovered buffer spring elastic deformation, the mechanical system can basically no loss, the total function before and after the two slider son collision constant available formula (7-2) By (71) and (7-2) combined solution available (7-3) In the experiment, if the M1 = m2, th