如图所示，理想变压器原线圈输入交流i=Imsinωt，副线圈按有一电流表和负载电

发布时间：2017-07-21 17:49 │ 来源：www.tikuol.com

题型：选择题

问题：

如图所示，理想变压器原线圈输入交流i=I_msinωt，副线圈按有一电流表和负载电阻R，电流表的示数为0.10A．在t=时（T为交流的周期），原线圈中的电流瞬时值为0.03A．变压器的原、副线圈的匝数比为（　　）

A．10：3

B．3：10

C．3：10

D．10：3

考点：交变电流的周期和频率交变电流的最大值、有效值、瞬时值和平均值变压器的结构和原理

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近来，一些抗日题材的电视剧为了提高收视率，粗制滥造，颠覆历史，将革命历史题材武侠化、快餐化，变为纯粹的娱乐品，罔顾公共理性。2013年5月17日，国家新闻出版广电总局对各卫视提出明确要求，对卫视电视剧黄金档已报排播的抗战题材剧进行重审和甄别，对存在过度娱乐化的抗战剧进行修改，停播不能修改的过度娱乐化抗战剧。这启示我们

A．历史传承应该坚持与时俱进

B．影视创作应该坚持百花齐放

C．文化建设需要弘扬民族精神

D．影视创作需要注重社会效益

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阅读理解。

Some students are talking about: Should the children of migrant workers (农民工) study in the cities
or in their hometowns? Here are their opinions.

Speaker	Opinions
	In the cities
Kangkang	The children of migrant workers could get better educations in the cities. The teachers and schools are better there. They could live with their parents, too.
Li Ming	Children should live with their parents. Parents can look after them well. The children of migrant workers may feel lonely if they stay in their hometowns. They may not go to school.
Wang Tao	Studying in a city doesn't only mean getting a better education, it means having much more chances in the city than in their hometowns. The kids see lots of things they wouldn't be able to see in their hometowns.
	In their hometowns
Lingling	It's easy for children to go to school in their hometowns. In the city, things are much more difficult. First, there are so few schools for the children of migrant workers. Second, their parents may have to change jobs often. This means the kids may have to change schools a lot too.
Han Mei	The children of migrant workers may find it hard to adapt (适应) to life in the city. In city school, they may get bullied (被欺负). Also, these children may fall behind because of the different levels (水平) of education.
Lily	Studying in the city costs a lot more than studying in the countryside. The cost may add to the burdens (负担) of the parents.

1. Kangkang'thinks the children of migrant workers may _________ in the city.

A. feel lonely
B. get fewer chances
C. get better educations

2. Who thinks that children should live with their parents?

A. Li Ming and Wang Tao.
B. Kangkang and Li Ming.
C. Wang Tao and Kangkang.

3. What's Lingling's opinion?

A. There are no enough schools for migrant workers' children in the city.
B. It's difficult for the children to go to school in their hometowns.
C. It is good for the children to change schools often.

4. Han Mei worries about the children of migrant workers _________.

A. may not go to school
B. may fall behind with their study
C. can't be looked after well

5. Lily is afraid that _________.

A. the children may made friends
B. the children can not get on well with their classmates
C. the migrant workers may pay much more money for their children's studying in the city

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沸腾炉燃烧的燃料主要是烟煤。

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有关靶器官的下列说法正确的是（）

A.脂肪组织是最常见的靶器官之一

B.靶器官一般只有一个，不可能有几个

C.在同一靶器官产生毒效应的化学物质毒作用机制相同

D.靶器官一定是该化学物质浓度最高的场所

E.苯胺和CO均可作用于红细胞，影响其运输氧的能力，但毒作用机制不同

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抗滑桩桩孔垂直度允许偏差为（）%。

A、1

B、2

C、3

D、4

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