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八年级物理上册4.4超声波练习2新版北师大版020190122417.doc

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1超声波1、蝙蝠通常在夜间出来活动、觅食，但它们从来不会撞击到墙壁、树枝上，并且能以很高的精确度确认目标这主要是因为（ ）A蝙蝠有夜视眼B蝙蝠靠嗅觉确定目标C蝙蝠靠听觉确定目标D蝙蝠在飞行过程中靠发出超声波遇到障碍物反射回来的声波确定目标2、关于超声波的利用，下列叙述中正确的是（ ）A利用超声波可以探测人体内脏器官的疾病B利用超声波可以探测海洋的深度C利用超声波可以直接清洗精密机械上的污垢D利用超声波可以除去人体内的结石参考答案：（1）D （2）A、B、D

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