题干

在探究声音的产生的实验中,将发声的音叉轻轻接触细线悬吊的轻质乒乓球,乒乓球被弹开,说明音叉在振动.以下几个实验中所用研究方法与其相同的是(  )

A:研究声音是由物体振动产生时,比较物体发声与不发声的区别

B:通过扬声器前蜡烛火焰的情况来判断声音是否具有能量

C:研究材料隔声性能时用同一声源,并在声源周围包上厚度相同的材料

D:研究光的直线传播时引入光线

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答案(点此获取答案解析)

B

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