题目内容
如图所示,m1、m2、m3三物体都处于静止状态,滑轮与绳之间的接触均光滑,连动滑轮的两绳与水平方向夹角分别为60°、30°,则m1、m2、m3的比值为: ( )
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241408324165698.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241408324165698.jpg)
A.1∶2∶3 | B.2∶1∶1 | C.2∶![]() | D.2∶1∶![]() |
C
动滑轮的受力情况如图:
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241408330402116.jpg)
由三角形的边角关系得:
;
。
故有:
,选C。
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241408330402116.jpg)
由三角形的边角关系得:
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824140833055810.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824140833133815.png)
故有:
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241408332111750.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
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