问题 多选题

质量为8kg的均匀木块,它与桌面的接触面积为100cm2,若用2N拉力使它在水平桌面上匀速前进1m,下列叙述错误的是(  )(g=10N/Kg)

A.木块与桌面之间摩擦力大小是2N

B.木块在运动过程中机械能增大了

C.拉力在此过程中做功是2J

D.木块对桌面的压强是800Pa

答案

A、物体在水平桌面上做匀速直线运动,且只受到拉力和摩擦力的作用,所以拉力和摩擦力是一对平衡力,即摩擦力等于拉力等于2N.故A的说法正确,不合题意.

B、物体在此过程中做匀速直线运动,速度大小不变,动能不变,高度不变,重力势能也不变,所以机械能不变.故B的说法错误,符合题意.

C、物体通过的距离L=1m,受到的拉力F=2N,所以拉力在此过程中做的功:W=FL=2N×1m=2J;故C的说法正确,不合题意.

D、由于物体是在水平桌面上,并且在竖直方向上不再受到其它的力的作用,所以物体对桌面的压力等于物体的重力,即F=G=mg=8kg×10N/kg=80N.

所以物体对桌面的压强:P=

F
S
=
80N
0.01m2
=8000Pa;故D的说法错误,符合题意.

故选BD.

选择题
完形填空

阅读表达。阅读下面的短文,并根据文章后的要求答题。(请注意问题后的词数要求)

A poet is in his words

The writings of William Shakespeare are today little read by young people in Britian. His young readership is limited to those who choose to study literature at university.

Still, in British schools, ____________ to study the poet, and when something is made compulsory, usually the result is boredom, resentment or both. Shakespeare, Chareles Dickens, Jane Austen-for many of the young, reading them can seem like being forced to eat medicine, especially when people are at an age when they are beginning to discover themselves and wanting to claim their independence.

This was my experience of the classics at school. But when I reached my late teenage years, I had a change of heart. Like every other young person since the dawn of time, the world confused me. I wanted answers, so I turned to books to find them.

I went on to take a PhD in literature and have taught the subject in universities in Britain and China. I have never regretted it. There is something in literature that people want, even if they don’t read books.

You see this in the popularity of TV and movie adaptations of great works, the recent film version of Jane Austen’s Pride and Prejudice being a case in point. These popular adaptations may help increase people’s interest in the classic.

Reading a simplified Romeo and Juliet may perhaps lead to a reading of Shakespeare’s actual play. If that is the case then I welcome the trend. But do not make the mistake of thinking that it is the same thing. Shakespeare is a poet and his greatness is in his language. Reading someone else’s rewriting of his work is like peeling (剥皮) a banana, throwing away the fruit, and eating the skin. Take on the original. It really is worth the effort.                                                                             

小题1:Find a sentence from the text which can explain the title.

___________________________________________________________________

小题2:Fill in the blank in Paragraph 2 with proper words to complete the sentence. (within 5 words)

___________________________________________________________________

小题3:Why are the adaptations of great works popular?

___________________________________________________________________

___________________________________________________________________

小题4:Do you think it necessary to read the original? Why? (within 30 words)

____________________________________________________________________________________________________________________________________

小题5:Translate the underlined sentence in the last paragraph into Chinese.

______________________________________________________________________________________________________________________________________