单摆测重力加速度实验的改进  

Improvement of the experiment using a single pendulum to determinegravitational acceleration

作　　者：刘彧奇 谭雨莎 韦先涛 张权 赵伟[2] 朱玲[2] LIU Yu-qi;TAN Yu-sha;WEI Xian-tao;ZHANG Quan;ZHAO Wei;ZHU Ling(School of Earth and Space Sciences,University of Science and Technology of China,Hefei,Anhui 230026,China;School of Physical Sciences,University of Science and Technology of China,Hefei,Anhui 230026,China)

机构地区：[1]中国科学技术大学地球和空间科学学院,安徽合肥230026 [2]中国科学技术大学物理学院,安徽合肥230026

出　　处：《大学物理》2021年第3期56-61,共6页College Physics

基　　金：中国科学技术大学教学研究项目(2019xjyxm076)资助。

摘　　要：在单摆测重力加速度实验中,很难对摆长进行非常精确的测量,在较好的测量条件下其测量精度一般也只能达到毫米量级,所测得重力加速度的相对误差一般在1%左右.针对这一问题,本文通过对单摆实验装置进行改进,利用与摆线连接在一起的游标卡尺精确测量摆长的改变量而不直接测量单摆摆长,可将测量精度提高到0.02毫米.同时利用光电门测量摆球摆动周期,并对不同的摆线材质和直径进行了对比实验和分析,在最佳条件下可将重力加速度的测量误差控制在0.1%以内.In the experiment of measuring the gravity acceleration by a single pendulum,it is difficult to determine the pendulum length very accurately.Under the better measurement conditions,the measurement accuracy could generally reach the order of millimeter,and the relative error of the measured gravity acceleration is generally about 1%.In order to solve this problem,in this paper the measuring precision was improved to 0.02mm by using avernier caliper connected with a cycloid to accurately measure the change of pendulum length instead of directly measuring the pendulum length.At the same time,the swing period of the pendulum ball is measured by a photoelectric gate,and the different cycloid material and diameter are compared and analyzed.The measurement error of acceleration is controlled within 0.1%.

关 键 词：单摆 重力加速度 摆线 摆长改变量 角振幅 

分 类 号：O4-34[理学—物理]