体育场的标准跑道是400 m,在进行100 m短跑比赛时,使用跑道的直道

体育场的标准跑道是400 m,在进行100 m短跑比赛时,使用跑道的直道部分,运动员跑完全程通过的路程和位移各是多少?如果一名运动员沿跑道跑了两周,他的路程和位移又是多少?

答案

解:当运动员沿直线跑时,运动员做直线运动,所发生的路程和位移的大小是相等的,所以均为100 m;而当运动员沿圆周跑两圈时,运动员做曲线运动,路程和位移的大小不再相等,路程为两个圆周的长,即800 m,运动员从起点运动到终点,起点与终点重合,所以运动员的位移为零。

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