题干

下列有关磁现象的四幅图中说法正确的是(   )

A:地球仪悬浮于磁铁上方静止,球体受到的磁铁斥力大于所受重力

B:蹄形磁铁周围小铁屑的分布情况说明磁感线是磁场中真实存在的曲线

C:闭合开关,同时对调磁极和电源正负极可以改变导线ab受力方向

D:线圈abcd在磁场中转动时,电路中会产生电流,小灯泡会发光

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D

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Be an inventor

    The biggest secret about inventing is that anybody can do it! Perhaps this sounds crazy, but it's true. Maybe you have the wrong idea about inventing, so read on to discover the truth.

Wrong idea number 1:____

    Well, inventing means creating something “new”, but the idea could come from something that already exists.____ 

Wrong idea number 2: Inventors are born, not made.

    There are a lot of factors that make invention possible. Take Mozart, for example. He was born with a special talent for music.____His father was a music teacher, and Mozart practiced for hours every day, from the time he was in kindergarten.

    ____Very successful creators don't give up when they get something wrong. As one inventor said, “A failure is the right answer to the wrong question!”

    Wrong idea number 3: Inventors are always old people.

____ Here is an example of a young inventor: Louis Braille went blind when he was a child. When he was 15, he invented a system of reading and writing for blind people that is still used in most countries today.

A. Everyday things can give people lots of ideas.

B. An invention has to be something completely new.

C. But other factors were also important for his creativity.

D. As a young man, George Nissen invented the trampoline (蹦床).

E. Don't believe that you can't invent something when you are young.

F. Thomas Edison said that being an inventor was “99% hard work and 1% inspiration”!

G. The Wright brothers, for example, got the idea for building a “flying machine” from watching birds.