题目内容
如图所示,放在斜面上的物体受到垂直于斜面向上的力F作用而物体始终保持静止.当力 F 逐渐减小,则
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250013153651912.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250013153651912.jpg)
A.物体受到的摩擦力保持不变 |
B.物体受到的摩擦力逐渐减小 |
C.物体受到的合力减小 |
D.物体对斜面的压力增大 |
AD
试题分析:对物体进行受力分析如图所示,
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250013153812735.jpg)
将所有的力沿着斜面与垂直于斜面正交分解,得
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825001315396751.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825001315412856.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825001315427744.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825001315459832.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目
题目内容
A.物体受到的摩擦力保持不变 |
B.物体受到的摩擦力逐渐减小 |
C.物体受到的合力减小 |
D.物体对斜面的压力增大 |