空气中声速随温度变化规律的简易实验

Home-based experiments of sound velocity varying with the temperature in air

空气中的声速随着温度的变化而变化,本文利用生活中的器材(有限长直管)自制简易实验装置,借助手机APP作为声音发射器和频率接收器,在管内中部区域形成恒温条件,实现了驻波法对不同温度下声速的测量,在测量范围内相对误差不超过2%.这种基于传统物理实验的拓展,在特殊居家环境下亦可进行,有利于物理实验线上自主学习模式的开展,促进学习者的综合素质和实践创新能力的提升.

The sound velocity in air varies with temperature. In this paper a finite length straight pipe is used to measure the sound velocity, and mobile APP is adopted as a transmitter and a receiver of sound wave. A constant temperature condition is fulfilled in the internal area of the pipe in order to accomplish the sound velocity measurements at different temperature by standing wave method. The relative errors of the measurements maintained to be less than 2%. This home-based experiment proposed in this paper is a prolongation of traditional physical experiments. It can be arranged as an online experiment during special epidemic period. It can also promote the comprehensive quality and the practical innovation abilities of students.