题目内容
如图所示,以直角三角形AOC为边界的有界匀强磁场区域,磁感应强度为B,∠A=60°,AO=a。在O点放置一个粒子源,可以向各个方向发射某种带负电粒子,粒子的电量大小为q,质量为m,发射速度大小都为v0,发射方向由图中的角度θ表示.不计粒子间的相互作用及重力,下列说法正确的是( )
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250047227753947.png)
A.若v0=
,则以θ=0°方向射入磁场的粒子在磁场中运动的时间为![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722806603.png)
B.若v0=
,则以θ=60°飞入的粒子在磁场中运动时间最短
C.若v0=
,则以θ<30°飞入的粒子在磁场中运动的时间都相等
D若v0=
,则在AC边界上只有一半区域有粒子射出
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250047227753947.png)
A.若v0=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722791657.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722806603.png)
B.若v0=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722822596.png)
C.若v0=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722822596.png)
D若v0=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722822596.png)
D
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250047228843978.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250047229153823.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/201408250047229312386.jpg)
试题分析:若v0=
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722791657.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722806603.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140825/20140825004722791657.png)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目