手机传感器测量重力加速度的方法与改进

Summary and improvement of mobile phone sensors to measure gravity acceleration

测量重力加速度是高中物理教学中必不可少的一个实验,智能手机已经普及,而运用智能手机内置传感器测量重力加速度的方法众多,该文拟通过实验筛选出适合课堂教学的方法.通过文献调研和还原实验,发现只用手机法、多普勒效应法和单摆法测量重力加速度具有测量简单、方便快捷、方法可行、有利于学生理解实验原理等优点,故这3种方法较为适合课堂教学,通过重复这3个实验,发现单摆法是最简便可行的适合于教学的方法.因此,该文重点对单摆法进行了改进,包括用磁化后的小球代替普通铁质小球,方便利用磁传感器记录周期;为了减少手拨动单摆的误差,运用夹子释放小球;为提高测量结果准确度,用鱼线作为摆线.

The experiment of gravity acceleration measuring is an important experiment in school physics teaching.Smartphones have become popular,and there are many ways to measure gravity acceleration using the built-in sensors of smartphones.This work was intended to screen out the suitable methods for teaching through experiments.Through literature research and experiment,it was found that using only mobile phone method,Doppler effect method and single pendulum method was feasible and beneficial for students to understand the experimental principle,so these three methods were more suitable for classroom teaching.By repeating these three experiments,it was found that single pendulum method was the most feasible method suitable for teaching.Therefore,this paper focused on the improvement of single pendulum method.Replace ordinary iron balls with magnetized balls,which made it easy to record cycles with magnetic sensors.In order to reduce the error of hand swinging single pendulum,use clips to release the ball.In order to improve the accuracy of the measurement results,fish wire was used as a swing line.