题目内容
如图,用两根等长轻绳将木板悬挂在竖直木桩上等高的两点,制成一简易秋千。某次维修时将两轻绳剪去一小段,但仍保持等长且悬挂点不变。木板静止时,F1表示木板所受合力的大小,F2表示单根轻绳对木反拉力的大小,则维修后
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250049067181507.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250049067181507.png)
A.F1不变,F2变大 | B.F1不变,F2变小 |
C.F1变大,F2变大 | D.F1变小,F2变小 |
A
试题分析:前后两次木板始终处于静止状态,因此前后两次木板所受合力F1都等于零,保持不变,C、D错误;绳子剪去一段后长度变短,悬挂木板时绳子与竖直方向夹角
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004906734297.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004906749794.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004906780353.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目