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问题 探究题

某同学要探究电阻的大小与哪些因素有关，供选择的导体规格如下表：

（1）为了完成所有的探究实验，应选择的一组导体是[ ]

A．③ ④ ⑤ ⑥

B．② ③ ⑥ ⑦

C．① ⑤ ⑥ ⑦

D．⑤ ⑥ ⑦ ⑧

（2）在实验中通过观察_________来比较导体电阻的大小

（3）选择编号为⑤、⑥的导体接在A、B两点间进行实验，分析数据可得结论为__________

（4）将编号⑥、 ⑦的材料接入电路，_____  (填“能”或“不能”) 探究电阻和长度的关系，这是因为__________。

答案

（1 ）C

（2 ）电流表示数（小灯泡亮暗程度）

（3 ）导体的长度和材料相同时，横截面积越大，导体的电阻越小

（4 ）不能；没有控制导体的横截面积相同

改错题

增加：在缺词处加一个漏字符号(∧)，并在其下面写出加的词。

删除：把多余的词用斜线(\)划掉。

修改：在错的词下画一横线，并在该词下面写出正确的词。

注意：1.每处错误及其修改均仅限一词；只允许改10处，从第11处起不计分。

Yesterday a schoolboy is daydreaming in class. With realizing what he was doing, he put a pen cap into his mouth. A few minutes late, he was terrified to find that he had swallowed it! The teacher was shocking when the boy stood up and said, “I have just swallowed a pen cap.” He was quickly sent the nearest hospital. There a doctor examined him and said the best treatment was to take some medicines so that the pen could pass natural. Three hours later, the boy successfully made it. “She is really lucky.” said the doctor. “It’s not rare that small children put things into their mouths for a fun. It is very danger.”[
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单项选择题

心肌梗死并发室壁瘤，主要见于（）

A.左心室

B.室间隔

C.右心房

D.右心室

E.左心房
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