http://s04110118.mfs1.edu.hk/question.doc
要有步驟..thx~~.
ce physics mc
2008-03-24 7:47 am
回答 (1)
2008-03-24 7:54 am
✔ 最佳答案
gain in potential energy of the man= mgh
= 60 x 10 x 18
useful power output
= energy/ time
= 60 x 10 x 18/ 80
so the answer is B
收錄日期: 2021-04-13 15:20:17
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20080323000051KK03463