本题目来源于试卷: Work Energy and Power，类别为 美国物理杯赛(Physics Bowl)
[单选题]
06.20: A boy jumps from rest straight upward from a flat, stationarynw y7 .wsyro a 2sxtfr(u(;:vzu8+3uh con)lze;jnc 6+t*0 gdim zcrete surface. The boy, of mass M, leaves the concrete surface with speed v and his center of mass rises a distance d to the highest point of the motion. How much physical work did the averamc+in* jd g; zel6z0)tge normal force of contact (N) between the boy’ s feet and the concrete do on the boy?
A. $Nd$
B. $0.5Mv^{2}$
C. $0.5Nd$
D. $Mgd$
E. $0$
参考答案: E
本题详细解析:
暂无
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