试题与答案

关自感电动势叙述正确的是()。 A.自感电动势的大小与线圈电感量成反比 B.自感电动

题型:单项选择题

题目:

关自感电动势叙述正确的是()。

A.自感电动势的大小与线圈电感量成反比

B.自感电动势的大小与通过线圈电流的变化率成正比

C.自感电动势的方向可用右手定则确定

D.自感电动势总是随着电流变化而变化

答案:

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题型:阅读理解

阅读理解。

     A small town in southwest Britain is banning (禁止) plastic bags in an attempt to help the environment

and cut waste-a step that environmentalists believe is a first for Europe.

      Shopkeepers in Mod bury population 1,500, agreed to stop handing out disposable plastic bags to

customers on Saturday. They said paper sacks and cloth carrier bags would be offered instead.

     Last month, San Franciso became the first U.S. city to ban plastic grocery bags. Internationally, laws

to discourage the use of plastic bags have been passed in parts of South Africa and Ireland, where

governments either tax shoppers who use them or fine companies that hand them out. Bangladesh already

bans them, and so do at least 30 remote Alaskan villages.

     Mod bury, about 225 miles southwest of London, has also declared a bag ammesty (宽限期), allowing

local people to hand in plastic bags that have piled up at home. They will be sent for a recveling. The Mod

bury ban was the idea of Rebecca Hosking, who saw the effect of bags on manne life while working in the

Pacific as a wildlife camerawoman. She said response (反应) in the town so far had been "really positive".

      "Mod bury is quite an old-fashioned town and a lot of people have wicker baskets to go out shopping

anyway," Hosking told Sky News Television.

    The World watch Institute, an environmental research agency, states that 100 billion plastic bags are

thrown away each year in the United States alone. More than 500 billion are used yearly around the world.

1. What was Rebecca Hosking?

A. A lawyer.

B. An environmentalist.

C. A sailor.

D. A photographer.

2. The underlined word "disposable" in the passage probably means _____.

A. acceptable

B. valuable

C. throw-away

D. long-lasting

3. It can be inferred from the passage that _____.

A. most of the people in Mod bury continue to use plastic bags

B. fewer and fewer plastic bags will be used in the world.

C. San Francisco is the first city to ban plastic bags in the world

D. most countries in the world have passed laws to ban plastic bags

4.Which of the following would be the best title of the passage?

A. Environmental Protection

B. Big Cities Banning Plastic Bags

C. Effect of Plastic Fags on Sea Animals

D. British Town Banning Plastic Bags

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