试题与答案

如图所示,ad、bd、cd是竖直面内三根固定的光滑细杆,每根杆上套着一个小滑环(

题型:不定项选择

题目:

如图所示,ad、bd、cd是竖直面内三根固定的光滑细杆,每根杆上套着一个小滑环(图中未画出),三个滑环分别从a、b、c处释放(初速度为0),用t1、t2、t3依次表示各滑环到达d所用的时间,则

[ ]

A.t1>t2>t3

B.t1=t2=t3

C.t1>t2=t3

D.条件不足,无法比较

答案:

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参考答案:地方铁路

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题型:阅读理解

阅读理解。

     Many people know the names Alexander Graham Bell and Thomas Edison. However, most people don't

know the name of the man who invented the television, Philo Farnsworth.

      Philo Farnsworth was born in 1906 and grew up on a potato farm. As a boy, he loved to learn about

science, and he read a lot of science books. When he was only thirteen years old, he drew a picture of a

machine that could send pictures as radio sends sounds. He got the idea from the way the potatoes were

planted in the field. The potatoes grew in long lines, side by side. This made a shape in Philo's mind. This

shape helped Philo think of a way to send the TV picture onto a piece of glass. But he was poor, so Philo

could not try to make his idea into a machine at that time.

      Later, Philo worked at many different jobs. He worked with trees. He worked on broken radios. He

worked on trains. He also worked as a street cleaner. At last, two rich men heard about his idea for television,

and they gave him the money to make it. On September 7th, 1927, they watched Philo test the machine he

built. When Philo turned on the machine, a small line could be seen on the glass. Philo said,"There you have it,

electric television."

     Later, a big company, RCA, said they had made the first television. Philo had to spend a lot of money on

lawyers to fight them. Finally, he won. Then, World War Two started in 1939. During the war, Philo spent a

lot of money helping the US army instead of building up his television company. After the war, other bigger,

richer companies started making televisions. In the end, Philo had to sell his company.

1. Why does the author mention Bell and Edison at the beginning of the text?

A. To remember both of them.

B. To prove their wisdom.

C. To introduce the topic of the text.

D. To explain their relationships.

2. According to the text, how old was Philo when he finished his invention of TV?

A. 27 years old.

B. 21 years old.

C. 33 years old

D. 39 years old

3. Philo Farnsworth got the idea for TV from ______.

A. the radio

B. science books

C. potato fields

D. a machine

4. The underlined part "building up" in the last paragraph probably means "______".

A. starting

B. sellin

g C. putting up

D. making bigger

5. Which is the correct order of the following events?

a. Two rich men gave Philo money to do experiments.

b. Philo sold his own company.

c. Philo beat RCA in law.

d. Philo fixed broken radios.

e. Philo showed his invention to others.

A. d, a, e, c, b

B. e, d, c, b, a

C. d, c, e, b, a

D. a, c, b, d, e

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