题目内容
(12分)如图所示,一带电粒子以速度v0沿上板边缘垂直于电场线射入匀强电场,它刚好贴着下板右边缘飞出.已知匀强电场两极板长为L,间距为d,粒子的重力忽略不计。求:
(1)如果带电粒子的速度变为
v0,则离开电场时,沿场强方向偏转的距离为多少?
(2)如果带电粒子的速度变为
v0,板长L不变,当它的竖直位移仍为d时,它的水平总位移为多少?
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250020501687872.png)
(1)如果带电粒子的速度变为
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050137344.png)
(2)如果带电粒子的速度变为
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050137344.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250020501687872.png)
(1)
;(2)
。
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050184470.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050199467.png)
试题分析:(1)粒子以v0入射时,
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050215645.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050231478.png)
粒子以
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050137344.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050309687.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050340617.png)
得
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050371605.png)
(2)粒子飞出电场后,速度反向延长交上板的中点,由相似三角形得
飞出电场后的水平位移
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050387328.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050402393.png)
粒子的水平位移
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825002050418733.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目