本题目来源于试卷: 2011 美国F=ma物理竞赛 F=ma physics competition，类别为 美国物理杯赛(Physics Bowl)
[单选题]
Jonathan applies a normal force that vyle;y)1u r)r qqqg27 zixj e:.cgs(; is just enough to keep the rope from sle:0m9bxo 5g tdxo ai7tsk/f:6ipping. Becky makes a small jump, barely leaving contact with the floor of the box. Upon landing on the box, the force of the impact causes the rope to start slipping from Jonathans hand. At what speed does the box 05b:e6fgo ko:/xasx97 d it mtsmash into the ground? Assume Jonathans normal force does not change.
A. $\sqrt{2 g H}\left(\mu_{k} / \mu_{s}\right)$
B. $\sqrt{2 g H}\left(1-\mu_{k} / \mu_{s}\right)$
C. $\sqrt{2 g H} \sqrt{\mu_{k} / \mu_{s}}$
D. $\sqrt{2 g H} \sqrt{1-\left(\mu_{k} / \mu_{s}\right)}$
E. $\sqrt{2 g H}\left(\mu_{s}-\mu_{k}\right)$
参考答案: A
本题详细解析:
暂无
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