题干

下列关于质点的说法中,正确的是(  )

A:放在水平地面上的木箱,在箱上角处用水平力推它,研究木箱绕箱下角的转动,木箱可看作质点

B:放在水平地面上的木箱,在箱高的中点处用水平力推它,研究木箱在水平地面上的滑动,木箱可看作质点

C:只要是体积很小的物体,不论研究该物体的何种运动,该物体一定可以看作质点

D:研究人造卫星环绕地球的运动,人造卫星可看作质点

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答案(点此获取答案解析)

B,D

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