试题与答案

航空母舰上一般有帮助舰载机起飞的弹射系统,已知舰载机在跑道上加速时的加速度为4.5m

题型:单项选择题

题目:

航空母舰上一般有帮助舰载机起飞的弹射系统,已知舰载机在跑道上加速时的加速度为4.5m/s²,若该飞机滑行100m时速度达到50m/s而起飞,则弹射系统使飞机具有的初速度为()

A.40m/s

B.30m/s

C.20m/s

D.10m/s

答案:

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参考答案:文中“性从地变,质与物迁”一句体现了全文的核心观点。

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