非完全弹性碰撞能量损耗及恢复系数的实验探究

EXPERIMENTAL STUDY ON ENERGY LOSS AND RESTITUTION COEFFICIENT OF INCOMPLETE ELASTIC COLLISION

碰撞是物体(或粒子)间极短时间相互作用的物理现象。生活中,“碰撞现象”十分普遍并且伴随能量损耗。为了响应“停课不停学”,探索物理实验教学不依赖实验室条件的新模式,本文引导学生利用智能手机传感器和计算机设备设计实验,对非完全弹性碰撞过程中小球的能量损耗和恢复系数进行探究。实验表明,能量损失率会随着小球初始下落高度的而增加,而在同一初始高度下,能量损失率则随着碰撞次数的增加而减小。恢复系数随着小球初始下落高度的增加而减小,但在同一初始高度下,恢复系数随着碰撞次数的增加而增加。另外,进一步引导学生从理论分析和实验探究两方面讨论空气阻力对本实验的影响。

Collision is a physical phenomenon,in which objects(or particles)interact in a very short time.In our daily life,“collision phenomenon”is very common and accompanied by energy loss.In order to respond to the“suspended class,ongoing learning”,a new mode of physics experiment teaching that does not rely on laboratory conditions is explored.This paper guides students to design experiments using smart phone sensors and computer equipment to explore the energy loss and restitution coefficient of a small ball in the process of incomplete elastic collision in which a ball falls freely to the ground.Experiments show that the energy loss rate increases with the initial falling height of the ball,but decreases with the increase of the number of collisions for the same initial falling height.The coefficient of restitution decreases with the increase of the initial falling height,but increases with the number of collisions at the same initial falling height.In addition,students are further guided to discuss the influence of air resistance on the experiment from two aspects of theoretical analysis and experimental exploration.