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问题 选择题

在下图各电场中，A点电场强度较大的是（　　）

A．

B．

C．

D．

答案

A、在负点电荷的同一个圆上的所有点的电场的大小都是相等的，但是它们的方向不同，所以A错误；

B、在正的点电荷的电场中，离电荷近的地方电场强度大，所以A的电场强度大于B点的，所以B正确；

C、在匀强电场中各个点的电场强度都相同，所以AB的电场强度相等，所以C错误；

D、电场线密的地方电场的强度大，电场线疏的地方电场的强度小，所以A的电场强度小于B的电场强度，所以D错误．

故选B．

阅读理解

阅读理解。

     This is Jim's room. It's small but very nice. There is (有) a chair, a desk and a bed in the room. A computer

and some books are on the desk. The bed is next to the desk. Under the desk, there is a baseball. His computer

game is under the bed. There is a photo of his family on the wall (墙). He likes his room.

1. There is _____ in the room.

A. a desk

B. two desks

C. three chairs

2. _____ are on the desk.

A. A book and a computer

B. A computer and some books

C. Some books and some computers

3. There is _____ under the desk.

A. a chair

B. a computer game

C. a baseball

4. There is _____ on the wall.

A. a photo of his classmates

B. a photo of his teachers

C. a photo of his family

5. The room is _____.

A. small

B. nice

C. small and nice

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单项选择题

单剂量包装的散剂，包装量在1.5g以上至6g的，装量差异限度为（）

A.±15％

B.±10％

C.±8％

D.±7％

E.±5％
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