摘要
工程中常用对称三线摆来测量不规则物体的转动惯量.测量前需预先调整3条摆线严格对称,并保证待测物体和上、下两盘三者的质心严格共线,而三质心共线在实验过程较难严格实现.为此,本文设计并制作了一种不对称三线摆,即将待测物体直接作为下盘,用3根摆线悬挂在上盘上即可.无论3个悬挂点是否对称,也无论摆线是否等长,只要保证3条摆线与质心轴平行,即可测得该物体绕质心轴的转动惯量.实验结果与理论值误差在±5%内的概率为77.78%,表明不对称三线摆可以用于一般刚体的转动惯量测量.
To measure the rotary inertia of the object especially in irregular shape,the threeline pendulum is one of the most common candidates in the engineering.In the system,three lines should be symmetrically distributed,while the mass centers of the object and two discs should be pre-adjusted coaxially,which is difficult to realize.So an unsymmetrical three-line pendulum is proposed and manufactured in the article,where the object is suspended to a circular disc with three lines.Whether the three lines are of the same length or not,and whether three hanging positions are symmetrically distributed,if only the three lines are parallel to the centroid axis of the whole system,the rotary inertia of the object could be measured.The probability of the error within 5percent between the experimental and theoretical rotary inertias would be as high as 77.78 percent,which means the unsymmetrical three-line pendulum is suitable to detect the rotary inertia of the arbitrary object.
出处
《物理与工程》
2016年第6期57-60,共4页
Physics and Engineering
基金
中国石油大学(北京)优秀青年教师研究项目(2462015YQ0603)
校级教改项目对本文的资助
关键词
不对称
三线摆
转动惯量
unsymmetical
three-line pendulum
rotary inertia
