问题 计算题

一列横波在x轴上传播,a、b是x轴上相距sab=6 m的两质点。t=0时,b点正好到达最高点,且b点到x轴的距离为4 cm,而此时a点恰好经过平衡位置向上运动,已知这列波的频率为25 Hz。

(1)求经过时间1s,a质点运动的路程;

(2)设a、b在x轴上的距离大于一个波长,求该波的波速。

答案

解:(1)质点a一个周期运动的路程s0=4A=0.16 m

1s内的周期数是

1s内运动的路程s=ns0=4 m

(2)波由a传向b,

波由b传向a,

 

阅读理解

阅读理解。

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