试题与答案

如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,

题型:多选题

题目:

如图为理想变压器原线圈所接交流电压的波形.原、副线圈匝数比n1:n2=10:1,串联在原线圈电路中电流表的示数为1A,下列说法正确的是(  )

A.变压器输出端所接电压表的示数为20V

B.变压器的输出功率为200W

C.变压器输出端的交流电的频率为50Hz

D.穿过变压器铁芯的磁通量变化率的最大值为20/n2Wb/s

答案:

BCD

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题型:阅读理解

World Wildlife Fund (WWF)and Greenpeace are two famous organizations in the world. They both aim at making our planet a better place to live.

World Wildlife Fund works to protect wild animals and plants. It began in Switzerland on September 11,1961.Now,it has offices in 100 countries and nearly 5 millions members all over the world. The members are from different groups ,including governments, business, scientists and farmers. They have played an active role in saving animals and rainforests. One recent WWF project is protecting the Amazon rainforest. WWF has done plenty of research to find creative ways that meet the need of both people and nature.

Greenpeace was set up in 1971,with an idea of working for world peace at the very beginning. Now it is active in protecting oceans, forests, and animals as well. It also calls for the use of clean energy, like wind power and solar power. Greenpeace has offices in 45 countries such as America and Canada. Its head office is in Netherlands. Greenpeace has about 3 million members at present. Small steps lead to big changes. It encourages more and more people to take action.

小题1:WFF has nearly ________million members.

A.3

B.5

C.45

D.100小题2:The head office of Greenpeace is in________.

A.Canada

B.America

C.Netherlands

D.Switzerland小题3:According to the passage, both WWF and Greenpeace______.

A.protect animals

B.do plenty of research

C.work for world peace

D.use more clean energy

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题型:单项选择题 案例分析题

政府作用的范围、内容、方式必须随着国家和社会发展的需要而变化。回答下列各题。

相比建设钢铁厂、发电站等,我国政府在保护环境、投资教育和建立社会保障体制等方面应加大投入。因为钢铁等行业正面临着过度投资后的产能过剩,而环境、教育、社会保障方面却有数以万亿计的财政缺口等待填补。这表明()。

①政府职能已发生了根本变化

②政府社会公共服务职能必须强化

③建设服务型政府具有必然性

④一切公共服务都应由政府提供

A.①②

B.②③

C.③④

D.②④

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