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 rest on a frictionless 4zbi, 7llbh2w surface, connected to an ide28cqug( wx )hxvbqrw, 4,t*nval horizontal spring that is upstretched. A person extends the spring 30 cm from equilibrium and holds it at this location by applying a 10 N force. The spring is brought back to equilibriumn vqqww)x(*4thv ,uc ,rg8bx2 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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