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> 某日电梯坏了，小悦只好从一层爬楼梯去十九层，设此人质量为50kg，爬到第十层的时候用了2min，休息了30s后，又花了2min爬到十九层．如果该楼每层高3.0m，则全过程中小悦克服重力做功的平均功率是（g取10m/s 2）（　　） A．0W B．100W C．112.5W D．105.6W

问题：

发布时间：2024-09-13

某日电梯坏了，小悦只好从一层爬楼梯去十九层，设此人质量为50kg，爬到第十层的时候用了2min，休息了30s后，又花了2min爬到十九层．如果该楼每层高3.0m，则全过程中小悦克服重力做功的平均功率是（g取10m/s ²）（　　）

A．0W B．100W C．112.5W D．105.6W

参考答案：

提问用户：5q***F4B

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