题目内容
如图所示,一个静止的质量为m、电荷量为q的粒子(重力忽略不计),经加速电压U加速后,垂直进入磁感应强度为B的匀强磁场中,粒子打到P点,OP=x,能正确反映x与U之间关系的是
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250031015331642.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250031015331642.png)
A.x与U成正比 | B.x与U成反比 |
C.x与![]() | D.x与![]() |
C
试题分析:带电粒子在电场中加速运动,根据动能定理得qU=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101580586.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101596721.png)
进入磁场后做匀速圆周运动,根据洛伦兹力提供向心力,则有:qvB=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101611536.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101627583.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101642947.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825003101549356.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目