问题
问答题
如图所示的电路图中,小灯泡L1、L2、电铃并联,开关S1控制整个电路.S2只控制电铃.按电路图将图中各元件用笔画线代替导线连成电路.
答案
采用“电流流向法”,电流从电源正极出发,依次串联开关S1、开关S2、电铃回到电源的负极,再将灯泡L1和灯泡L2分别并联在开关S1与电铃的两端即可,如下图所示:
如图所示的电路图中,小灯泡L1、L2、电铃并联,开关S1控制整个电路.S2只控制电铃.按电路图将图中各元件用笔画线代替导线连成电路.
采用“电流流向法”,电流从电源正极出发,依次串联开关S1、开关S2、电铃回到电源的负极,再将灯泡L1和灯泡L2分别并联在开关S1与电铃的两端即可,如下图所示:
从方框中选择适当单词并用其正确形式填空。
He took a lot of luggage(行李)with him. So I got __小题2:__ the train with him and helped him put__小题3:__ his luggage. There were a lot of people on the train. Some of them had no seats and they stood in the aisle(过道). When I __小题4:__to get off the train, one worker shouted, “The train is __小题5:___now. Please get on the train as __小题6:__ as possible.” Then many people tried to get on the train. It was __小题7:__ for me to move. Before I could get off, the train began to move. Then my friend said to me, “Why don’t you go to Beijing with __小题8:__ ? You will have a great time there.” I thought it was not a __小题9:__ idea. So I went to Beijing for the __小题10:__time. |