狗拉雪橇沿位于水平面内的圆弧形道路匀速行驶,下图为四个关于雪

狗拉雪橇沿位于水平面内的圆弧形道路匀速行驶,下图为四个关于雪橇受到牵引力F及滑动摩擦力f的示意图(O为圆心),其中正确的是(    )

答案

C

解析:沿弧形轨道匀速行驶即匀速圆周运动,拉力与阻力合力应指向圆心,且阻力应在轨迹切线上,故选C.

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