在图( a )所示的电路中,电源电压保持不变。闭合电键 S ,过一段时间后,电流表 A 1 的示数突然变小,但不为零。将电阻 R 2 与另一电阻 R 3 连( b )所示电路(两电路使用的电源相同),闭合电键 S ,发现电流表 A 2 的示数与电流表 A 1 的示数相同。若故障可能出现在电阻 R 1 、 R 2 、 R 3 上,则下列判断中正确的是( )
A.
电阻 R 1 可能是完好的。
B.
电阻 R 2 可能发生断路。
C.
电阻 R 3 一定发生短路。
D.
电阻 R 3 一定是完好的 。
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
微信内点击右上角“…”即可分享
反馈
参考答案:
举一反三
【简答题】1C. Listen to the passage and then fill in the missing information in the following summary. Thomas Edison was one of the world’s greatest inventors. He was born in Ohio in 1847. He had very little sc...
【简答题】Amy:Is someone here? Talia: Yeah, i'm here.What are you back here for? Amy: I forgot _______. Talia: Oh, by the way, _______ was looking for you. He said he knew you in college. His name was Bill. Amy...
【简答题】When a plane from London arrived at Sydney airport, workers began to 1.______ a number of wooden boxes which contained clothing. No one could account for the fact that one of the boxes was extremely h...