问题
选择题
A、B、C三质点同时同地沿一直线运动,其s-t图象如图所示,则在0~t0这段时间内,下列说法中正确的是( )
A.质点A的位移最大
B.质点C的平均速度最小
C.三质点的位移大小相等
D.三质点平均速度一定不相等

答案
由图象可知A、B、C三质点在0~t0这段时间内的位移相等,时间也相等,所以平均速度也相等,故ABD错误,C正确.
故选C.
A、B、C三质点同时同地沿一直线运动,其s-t图象如图所示,则在0~t0这段时间内,下列说法中正确的是( )
A.质点A的位移最大
B.质点C的平均速度最小
C.三质点的位移大小相等
D.三质点平均速度一定不相等
由图象可知A、B、C三质点在0~t0这段时间内的位移相等,时间也相等,所以平均速度也相等,故ABD错误,C正确.
故选C.
完形填空。 | ||||
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