探究转动惯量影响因素和角动量守恒的演示装置

On the Demonstration Device for Influencing Factors of Moment of Inertia and Conservation of Angular Momentum

角动量是大学物理课程中非常重要的物理量,角动量守恒定律也是自然界的普遍规律,在大学物理实验课程中有着较为重要的地位。基于对转动惯量概念、角动量概念、角动量定理、角动量守恒定律的研究、分析,本文设计了一种新型的、可以同时探究转动惯量影响因素和演示角动量守恒的物理实验装置。该装置采用的是上、下两层的设计理念,通过改变滑块质量及滑块质量分布相对转轴的距离,可以探究转动惯量的影响因素,同时,通过移动滑块改变上、下两层支杆的转动惯量,可以验证角动量守恒定律。该装置配有遮光片和光电门等器件,可以实现由定性到定量的演示,其优点是结构简单、现象直观、便于操作,有很好的实验价值。

Angular momentum is a very important physical quantity in college physics courses,and the law of conservation of angular momentum is also a universal law of nature,which plays an important role in college physics experiment courses.Based on the research and analysis of the concept of moment of inertia,the concept of angular momentum,the theorem of angular momentum and the law of conservation of angular momentum,this paper designs a new physical experiment device which can explore the influencing factors of moment of inertia and demonstrate the conservation of angular momentum at the same time.The device adopts the design concept of upper and lower layers.By changing the mass of the slider and the distance between the mass distribution of the slider and the rotation axis,the influencing factors of the moment of inertia can be explored.At the same time,by moving the slider to change the moment of inertia of the upper and lower support rods,the law of conservation of angular momentum can be verified.The device is equipped with light shielding sheet,photoelectric gate and other devices,which can realize the demonstration from qualitative to quantitative.Its advantages are simple structure,intuitive phenomenon,easy operation,and good experimental value.