问题
填空题
一汽艇在相距2km的甲乙两码头之间往返航行,逆水时用1.5h,顺水时用1h,则往返一次的平均速度为______,平均速率为______.
答案
往返一次的总位移为零,所以平均速度为零,
平均速率为
=s t
km/h=1.6km/h2+2 2.5
故答案为:0;1.6km/h
一汽艇在相距2km的甲乙两码头之间往返航行,逆水时用1.5h,顺水时用1h,则往返一次的平均速度为______,平均速率为______.
往返一次的总位移为零,所以平均速度为零,
平均速率为
=s t
km/h=1.6km/h2+2 2.5
故答案为:0;1.6km/h
选用方框内所给单词填空,使短文意思通顺、完整。注意:1 每个词限填一次2 每空限填一词,有些词需要做相应的变化。3 其中有两个多余选项。
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