下列说法中正确的是( ) A.体积、质量都极小的物体都能看成质点 B

下列说法中正确的是(  )

A.体积、质量都极小的物体都能看成质点

B.当研究一列火车全部通过桥所需的时间时,因为火车上各点的运动相同,所以可以把火车视为质点

C.研究自行车车轮转动时,不能把自行车视为质点

D.各部分运动状态完全一致的物体可视为质点

答案

CD

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