试题与答案

如图所示,AB是一质量为m的均匀细直杆,A端靠在光滑的竖直墙壁上,B端置于水平地

题型:选择题

题目:

如图所示,AB是一质量为m的均匀细直杆,A端靠在光滑的竖直墙壁上,B端置于水平地面上,杆身与竖直方向夹角为θ,杆与地面的摩擦系数为μ,保持平衡,则此时杆与地面的摩擦力为(  )

A.mgtgθ

B.mgsinθ

C.μmg

D.μmg

答案:

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参考答案:D

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题型:阅读理解

I will never forget what my old headmaster taught me. Normally when you are only 15          years of age you do not remember most of the things that are taught by your teachers. But this particular story is one such lesson that I will never forget. Every time I drift off course, I get reminded of this story.

It was a normal Monday morning, and he was making a speech to the students on important things in life and about devoting ourselves to what is important to us. This is how the story went:

An old man lived in a certain part of London, and he would wake up every morning and go to the subway. He would get the train right to Central London, and then sit at the street corner and beg. He would do this every single day of his life. He sat at the same street corner and begged for almost 20 years. His house was dirty, and a stench(恶臭)came out of the house and it smelled horrible. The neighbors could not stand the smell any more, so they asked the police officers to clear the place. The officers knocked down the door and cleaned the house. There were small bags of money all over the house that he had collected over the years.

The police counted the money, and they soon realized that the old man was a millionaire. They waited outside his house to tell the good news to him. When he arrived home that evening, he was met by one of the officers who told him that there was no need for him to beg any more as he was a rich man now, a millionaire. He said nothing at all; he went into his house and locked the door. The next morning he woke up as usual, went to the subway, got into the train, and sat at the street corner and continued to beg. Obviously, this old man had no great plans, dreams or anything important for his life. We learn nothing from this story other than staying focused on the things we enjoy doing.

59. The headmaster told the story to the students to__________.

A. make the students relaxed in the lesson             B. remind the students to think deeply

C. show how poor the old man was                            D. encourage the students to become rich

60. After hearing what the officer said, the old man_________.

A. believed the officer was playing a joke on him. B. didn't know many people respected him a lot.

C. was very angry to find his house broken into.     D. was not so excited as the officer had expected.

61. What did the author learn from the story?

A . One should devote himself to his dream.            B. The old man was foolish not to stop begging.

C. What the headmaster taught was very important.

D. People must have a plan before taking action.

62. Which word can best describe the author's attitude towards the old man?

A. Pity.           B. Disappointment.                 C. Respect.          D. Anger.

63. We know from the passage that ___________________.

the author had a big dream at the age of 15.         

B. the headmaster was popular with the students.

the old man begged every day without stopping.  

D. the neighbors took great pity on the old man.

BDACC 

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