题目内容
在倾角为37°的斜面上,从A点以6m/s的初速度水平抛出一个小球,小球落在B点。如图所示,求小球刚碰到斜面时的速度方向(可用速度与水平方向夹角的正切表示)、AB两点间的距离和小球在空中飞行的时间。(g=10m/s2)![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241231171941961.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241231171941961.jpg)
运动轨迹如图,设小球运动的时间为t,利用平抛知识有
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117225364.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117241466.gif)
结合几何知识:![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117257498.gif)
联立解得:
s
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241231172881778.jpg)
AB两点间的距离
m
小球落到斜面上时,竖直方向的分速度
m/s
则,速度与水平方向的夹角的正切![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117584586.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117225364.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117241466.gif)
结合几何知识:
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117257498.gif)
联立解得:
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117272554.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241231172881778.jpg)
AB两点间的距离
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117303610.gif)
小球落到斜面上时,竖直方向的分速度
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117491423.gif)
则,速度与水平方向的夹角的正切
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824123117584586.gif)
略
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目