如图所示，套在条形磁铁外的三个线圈，其面积S1＞S2=S3，且“3”

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问题选择题

如图所示，套在条形磁铁外的三个线圈，其面积S₁＞S₂=S₃，且“3”线圈在磁铁的正中间．设各线圈中的磁通量依次为φ₁、φ₂、φ₃则它们的大小关系是（　　）

A．φ₁＞φ₂＞φ₃

B．φ₁＞φ₂=φ₃

C．φ₁＜φ₂＜φ₃

D．φ₁＜φ₂=φ₃

答案

答案：C

填空题

用所给单词的正确形式填空。

1. Last football match was very ________ (excite).

2. ________ (stay) up late is bad for your health.

3. Why don't you ________ (give) up smoking?

4. My parents didn't feel ________ (good) last Sunday.

5. ________ (not walk) on the lawn. We must protect (保护) our environment.

名词解释

四国条约