本题目来源于试卷: Circular Motion，类别为 美国物理杯赛(Physics Bowl)
[单选题]
05.28: A mass, M, is at sg3q;f5 w,a 8m ca*h9jbh-ghy rest on a/ /ayfw7rf cp m22 m-rzk2xpm0 frictionless surface, connected to an ideal horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this locat72f k c/-z0f/mp 2xymrrwmap2 ion by applying a 10 N force. The spring is brought back to equilibrium and the mass connected to it is now doubled to 2M. If the spring is extended back 30 cm from equilibrium, what is the necessary force applied by the person to hold the mass stationary there?
A. 20.0 N
B. 14.1 N
C. 10.0 N
D. 7.07 N
E. 5.00 N
参考答案: C
本题详细解析:
暂无
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