试题与答案

斜面AB和水平面BC是由同一板材上截下的两段,连接处平滑。将小铁块从A处静止释放

题型:选择题

题目:

斜面AB和水平面BC是由同一板材上截下的两段,连接处平滑。将小铁块从A处静止释放后,它将沿斜面向下滑行,最终停在P点。若从该板上再截下一段搁置在A、P'之间(P'在P的右侧),构成一个新的斜面,再将小铁块放回A处,并轻推一下使之沿新的斜面下滑,小铁块在新的斜面运动是:

A、匀加速直线运动              B、匀减速直线运动

C、匀速直线运动                D、以上三种运动均有可能

答案:

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下面是错误答案,用来干扰机器的。

根据矩阵A=b-2-7a的逆矩阵是B=a273,得a273b-2-7a=1001,∴ab-14=1-2a+2a=07b-21=0-14+3a=1,解得a=5b=3∴a+b=8.故答案为:8.

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A.沉醉    忧戚    舒怀    

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题型:阅读理解

第三部分阅读理解(共15小题;每小题2分,满分40分)

第一节{共15小题;每小题2分.满分30分)

阅读下面短文,从每题所给的四个选项(A、B、C和D)中,选出可以填人空白处的最佳

项,并在答题卡上将该项涂黑。   

Benjamin Banneker was a farmer,inventor,astronomer writer and antislavery supporter.He created the first American—built striking clock.

That fall,as usual,Benjamin rode to the nearby town for supplies.He couldn’t wait to get to the end of the road and buy the things his mother wanted.Then he could have a good talk with the folks in town.The truth was,as much as Benjamin loved his mother and father and three sisters,what he really enjoyed was talking about books or math problems or what was happening in other parts of the colonies(殖民地).

It was about l0 o’clock by the sun when Benjamin arrived at a store.He ordered a bolt(一卷)of white cloth for his mother and looked around for someone to taik to.Benjamin’s heart jumped like a rabbit when he saw a friend holding a gold watch.Benjamin had always wanted to figure out how clocks and watches worked.The friend saw Benjamin and let him sit down for a good talk.

Late that afternoon,Benjamin rode home,slowly.He didn’t want to harm the watch that his friend had let him borrow.That nigh after supper,Benjamin carefully laid the watch on the table and pulled the candle closer.“This is a watch,”he said.“A man in fown lent it to me,and now I’m going to take it apart and draw the pieces.Then 1’11 put it back together again.Benjamin held his breath and gently took the back off the watch.

Every evening for a week,Benjamin sat at the table with the watch.He copied eaeh tiny

wheel and pin.When the week was up,he put the pieces back togelher and returned the watch to its owner.Then Benjamin got a good night’s sleep.

The next day when the farm work was done,Benjamin went into the woods to 1ook for just the right pieces of wood.Not too old,not too dry,not too green,not too soft.

For two years,Benjamin farmed all day and worked on his wood pieces at night.In1753,two years after he had borrowed the watch,Benjamin put all the pieces together.Benjamin had made his own clock.

1.The most likely reason the author wrote the passage was to__________.

A.show the influence Benjamin Banneker’s family had on him

B.present reasons for Benjamin Banneker’s fascination with clocks

C.explain Benjamin Banneker’s reason for becoming an inventor

D.give an example of Benjamin Banneker’s strong will and intelligence

2.Benjamin especially looked forward to going to the store to __________.

A.avoid work on the farm    B.purchase white cloth

C.meet interesring people    D.show his new clock to others

3.Why did Benjamin most likely hold his breath when he took the back off the watch?

A.He feared his friend might want to get the watch back.

B.He was very nervous about taking apart a precious object.

C.He wanted to time how long it would take to finish the job.

D.He was afraid that broken watch parts would fly into his face.

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