本题目来源于试卷: gc physics textbook chapter 6 problems，类别为 IB物理学
[问答题]
A woman swimming upstream is not xm sgu8pec7 45l:5c;ngf6vypcaa9u )k7 vc-zmoving with respect to the uc4qs u,am,gg*d4n: gshore. Is she doing any work? If she stops swimming ,gd4sau*m ,qg4nu :cg and merely floats, is work done on her?
参考答案:
The woman does work by moving the water with her hands and feet, because she must exert a force to move the water some distance. As she stops swimming and begins to float in the current, the current does work on her because she gains kinetic energy. Once she is floating the same speed as the water, her kinetic energy does not change, and so no net work is being done on her.
本题详细解析:
暂无
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