题干

在水平地面上固定一个竖直轻弹簧,现在弹簧上端放一个重为10N的木块后,弹簧被压缩了2cm,系统处于平衡状态,则轻弹簧的劲度系数为(  )

A:2000N/m

B:500N/m

C:50N/m

D:20N/m

上一题 下一题 0.0难度 选择题 更新时间:2013-03-19 07:52:54

答案(点此获取答案解析)

B

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                                                                      Winners Club
   Winners Club is a bank account (账户) specially for teenagers. It has been sep up to help you better manage your money. The club is a bank account where you receive a key-card, so you can enjoy dealing with your money 24/7 — that's 24 hours a day, 7 days a week!
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