关于曲线运动,下列说法正确的有(     ) A.做曲线运动的物体

关于曲线运动,下列说法正确的有(     )

A.做曲线运动的物体速度方向在时刻改变,故曲线运动是变速运动

B.做曲线运动的物体,受到的合外力方向在不断改变

C.物体做圆周运动,它所受的合外力不一定指向圆心

D.物体只要受到垂直于初速度方向的恒力作用,就一定能做匀速圆周运动

答案

AC

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