题目内容
如图,当开关S闭合时,如果滑动变阻器滑动触头向左滑动,安培表和伏特表的示数变化应是:( )
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241525439394435.jpg)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241525439394435.jpg)
A.![]() ![]() |
B.![]() ![]() |
C.![]() ![]() |
D.![]() ![]() |
A
试题分析:当开关S闭合时,如果滑动变阻器滑动触头向左滑动,
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152544922349.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545015549.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545078304.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152543955216.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545327507.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545437348.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545437348.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545686541.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152545811377.png)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824152544111214.png)
故选A
点评:动态问题分析思路总体来说是按照先部分后整体再部分的顺序,要充分利用电路中不变部分的电阻不变的特点,间接地讨论电路变化部分.还要注意电源是有内阻的。
![](http://thumb2018.1010pic.com/images/loading.gif)
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