如图,两根相互平行的长直导线过纸面上的M、N两点,且与纸面垂直,导线中通有大小相

题型:选择题

问题:

如图,两根相互平行的长直导线过纸面上的M、N两点,且与纸面垂直,导线中通有大小相等、方向相反的电流.a、O、b在M、N的连线上,O为MN的中点,c、d位于MN的中垂线上,且a、b、c、d到O点的距离均相等.关于以上几点处的磁场,下列说法正确的是(    )

A.O点处的磁感应强度为零

B.a、b两点处的磁感应强度大小相等,方向相反

C.c、d两点处的磁感应强度大小相等,方向相同

D.a、c两点处磁感应强度的方向不同

考点:磁感应强度
题型:选择题

单词拼写(共10小题; 每小题1分,满分10分)

根据所给汉语提示选用适当的单词完成句子,每空仅限一词。

1. In Pride and Prejudice five sisters overcome __________ (障碍) to their happiness and marriage.

2. If you want to know how to study____________ (高效率地), come and join our club.

3. As Mr Darcy continued in his __________ (傲慢自大的) way, Elizabeth forgot his feelings.

4. During an interview, all questions should be asked in a logical __________ (顺序).

5. My brother attended practically every lecture and __________ (研讨会) when he was a

student.

6.All my household goods are __________ (保险) against accidental damage.

7. He joined the army for a time as a ____________ (外科医生) and went on an expedition to

Portugal.

8. Hiring a car will allow you to be __________ (灵活的) about where you visit and how long you stay.

9. This land is used by local people for __________ (放牧) their animals.

10. He is __________ (跛的) in one leg and walks with the help of a stick.

题型:选择题

李强叔叔的果园里有48棵苹果树,每棵苹果树大约有720个苹果,6个苹果大约重1千克.

(1)把这些苹果装入每箱装15千克的纸箱里,需要多少个包装箱呢?

(2)如果把这些苹果按每箱30元的价钱批发出去,果园能收入多少元?

题型:选择题

由于水和电解质平衡紊乱可致()。

A.热射病

B.热痉挛

C.热衰竭

D.中暑

E.休克

题型:选择题

免疫抑制剂不适用于下列哪种情况()。

A.艾滋病

B.类风湿性关节炎

C.系统性红斑狼疮

D.抗移植物排斥反应

E.超敏反应性疾病

题型:选择题

冷换系统的开工顺序,冷却器要先进冷水,换热器要先进冷油。

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