质点作曲线运动从A到B速率逐渐增加,如图,有四位同学用示意图表

质点作曲线运动从AB速率逐渐增加,如图,有四位同学用示意图表示AB的轨迹及速度方向和加速度的方向,其中正确的                 

答案

D

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