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速度与机械运动

> 一个自动扶梯在40s内可以把站在扶梯上的人送到楼上，如果扶梯停开，人走上去需用120s，那么当人仍以原来的速度沿着开动的扶梯走上去，需要 A.0.5 h B.20 s C.30 s D.0.3 h

问题：

发布时间：2024-09-09

一个自动扶梯在40s内可以把站在扶梯上的人送到楼上，如果扶梯停开，人走上去需用120s，那么当人仍以原来的速度沿着开动的扶梯走上去，需要

A.0.5 h
B.20 s
C.30 s
D.0.3 h

参考答案：

提问用户：0x***jrc

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