题目内容
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241205042751229.gif)
如图15-4所示,在匀强磁场中有一个“”形导线框可绕AB轴转动,已知匀强磁场的磁感强度B=
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504290406.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504306215.gif)
(1) e=10
cos100πt(V) (2)不能正常发光,8.3W
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504321225.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/201408241205042751229.gif)
(1)注意到图示位置磁感线与线圈平面平行,瞬时值表达式应为余弦函数,先出最大值和角频率。
ω=2πn=100πrad/s
ε
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504353177.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504290406.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504321225.gif)
所以电动势瞬时表达式应为e=10
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504321225.gif)
(2)小灯泡是纯电阻电路,其电阻为R=
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504415663.gif)
首先求出交流电动势有效值ε=
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504446391.gif)
恒定电流电路,如图15-5 所示,显然由于R=r,
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504462413.gif)
![](http://thumb.1010pic.com/pic2/upload/papers/20140824/20140824120504477577.gif)
![](http://thumb2018.1010pic.com/images/loading.gif)
练习册系列答案
相关题目