题目内容
在如图所示的电路中,电源内阻不计.为使电容器的带电量增大,可采取以下那些方法:( )
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241650242135875.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241650242135875.jpg)
A.增大R1 | B.增大R 2 |
C.增大R 3 | D.减小R1 |
BD
试题分析:直流电路中,电容器相当于断路,电容器两极板间电压等于电阻R2两端的电压;
根据电容的定义式
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824165024291575.png)
根据串联电路分压式
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824165024478624.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824165024665575.png)
故选BD.
点评:本题关键是根据分压式得到电容器两端的电压情况,然后根据电容的定义式确定电量的变化情况;本题中电阻R3两端电压为零,故电容器两端电压等于电阻R2两端电压.
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目