如图所示，一矩形线圈用细线吊起来，其中一边位于蹄形磁体中。 _爱下问搜题

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问题实验题

如图所示，一矩形线圈用细线吊起来，其中一边位于蹄形磁体中。

闭合开关，线圈向右摆动，断开开关后，再次闭合，线圈再次向右摆动。该现象说明

。

将开关断开，把电源正、负极接线对调，闭合开关，线圈向左摆动，重做一遍实验仍如此，该现象说明

。

（3）断开开关，将蹄形磁体N极和S极位置换一下，N极在下，S极在上，闭合开关，线圈向右摆动。与前面（2）中情况对比，说明_______________________________________。

答案

试题考查知识点：通电导线在磁场中会受到力的作用。

思路分析：这是对“通电导线在磁场中会受到力的作用”实验的简单回放。

具体解答过程：

（1）通电导体在磁场中要受到力的作用。

（2）通电导体在磁场中受到的力的方向和导体中电流方向有关。

（3）通电导体在磁场中受到的力的方向和磁感线方向有关。

试题点评：电和磁这类的题目新课标要求比较简单。

单项选择题 A1/A2型题

肝脏多发大囊性病变，囊中见囊，最可能是下列哪种病（）

A.肝棘球蚴病

B.肝囊肿

C.肝脓肿

D.肝吸虫病

E.肝海绵状血管瘤

完形填空

阅读下面短文，掌握其大意，然后从各题所给的四个选项中，选出最佳选项，并涂在答题卡上。
My mother used to ask me what was the most important part of the body. Through the years I would   21  what I thought was the correct answer. When I was younger, I thought   22  was very important to us as humans, so I said, “My ears, Mommy”. She said, “No. Many people are   23 . But you keep thinking about it and I will ask you again soon.”
Several years passed   24  she asked me again. Since making my first   25 , I had often thought of the correct answer. So this time I told her， “Mommy, sight is very important to everybody, so it must be our eyes.” She looked at me and told me, “You are   26  fast, but the answer is not correct because there are many people who are blind.”
27  the years, Mother asked me a couple more   28  and always her answer was, “No, but you are getting   29  every year, my child.” Then last year, my Grandpa died. Everybody was crying when it was our   30  to say our final good-bye to Grandpa. Mom asked me, “Do you know the most important body part yet, my dear?”
I was   31  when she asked me this now. I always thought this was a   32  between her and me. She saw the   33  on my face and told me, “This question is very important. It shows that you have really   34  your life.” I saw her eyes well up with tears. She said, “My dear, the most important body part is your   35 .” I asked, “Is it because it holds up your head?” She replied, “No, it is   36  on them a crying friend or loved one can rest their head. I only hope that you have enough   37  and friends that you will have a shoulder to cry   38  when you need it.” Then and there I knew the most important body part is not a   39  one. It is sympathetic to the pain of   40 .