声速测定实验中次极大现象的次频因素定量探讨  

Quantitatively discussion of the sub-maximum phenomenon in sound velocity experiment

作　　者：赵洁[1] 邱菊[1] 崔丽彬[1] 张荫民[2] 薛红玲[1] 

机构地区：[1]北京工业大学实验学院,北京101101 [2]北京信息科技大学光电信息与仪器北京市工程研究中心,北京100192

出　　处：《大学物理》2016年第1期35-38,共4页College Physics

基　　金：北京市工程研究中心开放课题(Q5024000201301);北京工业大学实验学院教研项目资助

摘　　要：大学物理实验中的声速测定实验,对理解波叠加和驻波的知识有重要作用.但共振干涉法中出现的"次极大"现象,极易造成实验操作的误判.本文针对这一现象进行了定量探讨.通过Matlab数值仿真和信号发生器信号的傅里叶频谱分析,并与实验数据对照,得出结论:"次极大"现象不是由"次频"共振引起.The experiment of measuring sound velocity in university plays the important role in comprehending the knowledge of wave superposition and standing wave. However, the sub-maximum phenomenon existing in the resonance interference method usually results in mistakes during experiment.This paper discusses quantitatively this phenomenon.Based on the numerical simulation of Matlab software, Fourier spectrum analysis of the information pro- duced by signal generator,and compared with the experiment data, the conclusion is that the sub-maximum phe- nomenon is not related with the sub-frequency signal.

关 键 词：超声波 驻波 声速测定 次极大 定量 

分 类 号：O422.1[理学—声学]