本题目来源于试卷: Physics Unit5: Circular Motion & Gravitation，类别为 通用国际物理
[单选题]
A stone, of mass m, is attached to a strong string and whirlql e8nydru6.3 ed:x.e-qo1ik7q,dui9c- hf+ eii uasm 8 in a vertical circle of radius r. At the exact top of the path the tension in the string is 3 times the stoneo.7,cie iq k:dus1uheqxf9 i8m- a+ -i's weight. The stone's speed at this point is given by
A. $2\sqrt{gr}$
B. $\sqrt{2gr}$
C. $\sqrt{gr}$
D. $2gr$
参考答案: A
本题详细解析:
暂无
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