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1.____is known to us all, things can easily go wrong when people are under______. A. Which;control    B. As; load     C. It; strength     D. As; stress 2.  ____ the storm on the sea, it is reported that the president has put off the trip.   A. thanks to      B. because of    C.due to       D. as a result 3.----- This is the second time I____ pictures with my own camera.  ----- It’s time that you ____ a picture of me.   A. had taken; took B. have taken; took  C. will take; will take D. took; have taken 4. You know nursing is____ a way of life.  A.as a much job as  B. as much a job as C. so job a much as D. a job so much as 5.---- The price is fine with me. How would you like ____ paid?  ----- Well, it’s up to you.   A. this        B.that        C. it        D. one 6. Will you see____ he can return the book to me?   A. it         B.it to         C.what       D.where 7. I love____ when people sing a song with much work done.   A. that        B. this         C. it        D. them 8.The parents feel hopeless when their son has_____ internet games for so long.   A. accustomed to   B.addicted to   C. been accustomed to  D.been addicted to 9. My payment rose_____10% in April_____ the same month last year.   A.in; compared to B. by; compared with C.in; compared with D. by; compared to 10. I’m putting on weight. The doctor has warned me to______ suggar.   A. keep up       B. keep fit      C. keep off      D.keep on 11. I send you books today, the rest_____ in a few days.   A. follows       B. followed      C.will follow     D. to follow 12.I have worked with children, so I know _____ to expect in my job.   A. what         B. how        C. where       D.why 13. It was great joy___ he recieved the news ___ his lost daughter had been found.   A. when; which      B. that; that      C.because      D.which;that 14. He is not______. He is the______ man in the streets.   A. somebody; average             B.somebody; common  C.something; ordinary            D.anyone; general 15. His landlady gave him a week's _____ to leave the flat. A. threat       B. notice        C. advice       D. information 16. Even if they are on sale, these refrigerators are equal in price to, if not more expensive than, _____ at the other store. A. those       B. the others       C. that        D. the ones 17. When I took his temperature, it was two degrees above _____. A. average      B. ordinary        C. regular       D. normal 18. Working hard is not only a_____ of a great success, but is among the essential requirement.  A. sign       B. signal        C. guarantee     D. marks 19.If you want to____, you must learn to work hard while you are still young.   A. make your way   B. make its way    C. make a way    D.make the way 20. I have to __my diet rather than eat the same all the time.,so that I can keep fit.   A. differ        B.vary        C. contiune      D. range 21.They are determined to work out the task,____difficult it is.   A. however      B.no matter what    C.no matter what   D.whatever      22, -----If I wasn’t busy., I could have been back by 5:30 o’clock.   ----- What a pity! She____ here to see you.   A. is         B. was         C. had been     D.has been 23._____ you keep on working hard, I don’t mind whether you get  good marks in your class.  A. As long as     B. As soon as      C. As well as    D.as far as 24.I really don’t know for certain__ they discussed.this important event very secretly.   A. where was it that B. where it was that C. where that D. it was where that 25.These desks and chairs can be ___ to the height of any child.   A. adjusted      B. adapted        C. fit       D.adopted 26.. With the change of the economic foundation the entire immense superstructure is _____ rapidly transformed. A. anything but    B. more or less     C. at large     D. any more 27 ------ I ‘m going to join them in the play. ------- ______. A. Have a pleasure  B. That’s a very nice of youC. Have fun   D. Have a fun 28. Do tell me the way you think of_____ the problem as soon as possible.    A. to solve     B. solving        C. solve     D. being solved 29 . The author of the report is well _____ with the problems in the hospital because he has been working there for many years.   A. acquainted    B. informed       C. known    D. advised 30.I wanted nothing but _____,_____ I stayed up all the night.     A. sleep; for     B. sleep; so      C.to sleep; so   D. to sleep; for 31.You’d better put the papers and magazines into_____ bag.    A. the paper     B. a paper       C. the paper’s    D.paper 32. Will you like there______ a meeting to disscuss the matter?    A. be        B.being       C. to be       D.is 33. We should unite, for no country _____can solve the problem of the pig flu.    A.alone;for      B.lonely; because   C. only; since    D. simply; as 34. While living in a foreign country, one__ a special dish from home now and then.    A. wishes       B. hopes       C. desires      D.cooks 35. Try to_______ at least an hour every day for learning English.    A. set off       B. set out       C.set about     D. set aside 36. I’m very hungry and_____ starving.    A. eventally     pletely     C. absolutely    D. especially 37.The old man was tired and walk more slowly but he home_______.    A. after all      B. at all        C. above all    D. in all 38.Most plastic don’t readily ______ heat and electricity.    A.attract       B.absorb        C.carry    duct 39. I’m surprised to see that he has an_____look on his face.    A. absent       B. absolute       C.academic   D. absorbent 40. With the development of socity,fewer and fewer old man is____ in the countryside.    A. abandoned    B.to abandon       C. abandoning  D.being abandoned 41.Government officialsare______ people and they should____the people heart and soul.   A. servants of; serve          B.service for; serve        C. servants of; serve for        D.servants for; serve of 42,The teacher is not easy-going,and he never ____in the pupils’ games.    A.took part     B.joined      C. participates     D. succeeds 43.Parts of graduations failed to seek a job without experience ,though they are ___ to get one.   A. fighting     B.looking forward   C. dying       D.hoping 44.---- My parents said that we would take a camping on May Day.   -----_____ it rains then?    A.What if     B.What about     C. What for     D. So what 45. It is clear that the whole world is passing through a social revolution in which a central _____ must be taken by scientists and technologists.   A. process     B. attention      C. measure      D. part 46. The boss strongly_____ me to their company for the job. A. advised     B. suggested     C. recommended   D. asked 47.Don’t worry about the present situation in the world;____ of people prefer peace to war.   A. Most      B. a great many    C. the majority    D.the number 48. The farmers were more anxious for rain than the people in the city because they had more _____.   A. at length    B. at last   C. at stake    D. at ease 49.I believed, though I could be mistaken,______ he liked me.    A.that       B.what        C.which       D.where 50. The man is____ a serious nervous breakdown because he is unable to deal with pressure from daily life.  

A.at the edge of    B. on the edge of    C.on behalf of   D. on the top of

试题详情

31.(8分)小明、小亮和小敏共同设计了一种测定水平方向风力的装置,其原理如图甲所示.绝缘轻弹簧的左端固定在O点,右端与中心有孔、表面竖直的金属迎风板相连,一起套在左端固定在O点的粗细均匀、电阻随长度均匀变化的水平金属杆上,迎风板与金属杆接触良好.电路中左端导线与金属杆的左端相连,右端导线连接在迎风板上并可随迎风板一起移动,R是定值电阻,a、b、c、d为四个接线柱.

(1)在他们的设计中,若要求在风力增大时,接入电路的电表的示数也随之而增大,则应该                               (   )

    A.只在a、b之间接电流表

    B.只在c、d之间接电压表

    C.在a、b之间接电流表,在c、d之间连接导线

    D.在c、d之间接电压表,在a、b之间连接导线

   (2)为了较准确的测出水平方向风力的大小,三位同学先对选定的轻弹簧和金属杆进行了两项测量.

    ①小明利用测量的数据作出了原长为40cm的轻弹簧的长度与所受压力F的关系图象(如图乙所示).由图可知:该弹簧每缩短10cm,弹簧受到的压力将增加____N.

    ②小亮和小敏设计了如图丙所示的电路,用来测量长度为50cm的金属杆的电阻.他们备选的部分器材有:

    A.电源(能够提供3V的稳定电压)

    B.电流表A(量程0-0.6A)

    C.电压表V(量程0-3V)

    D.滑动变阻器R1 (阻值变化范围为0-5)

    E.滑动变阻器R2 (阻值变化范围为0-10)  

    选好器材后,小亮和小敏在实验中正确操作,他们记录的测量数据如下表:

实验次数
1
2
3
4
5
A表示数I/A
0.2
0.3
0.4
0.5
0.6
V表示数U/V
1.0
1.5
2.0
2.5
3.0

根据他们的测量数据可以知道:他们实验中选用的滑动变阻器是_________(填器材

   的序号字母),他们测出的金属杆的电阻为_________

   (3)三位同学最后根据(1)的要求,按图甲进行组装时,除用到上述选定的轻弹簧、金属杆和(2)中备选的电源、电表外,还选了阻值R=3的定值电阻.如果无风时,迎风板离O点的距离以及轻弹簧的长度均等于弹簧的原长,则该装置能够测量的最大水平风力是__________N.

   (4)对小明、小亮和小敏设计的测定水平方向风力的装置,从力的角度,请你指出可能对测量准确度产生影响的因素之一:___________________________________.

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30.(7分)小丽为测量小灯泡的电功率进行了有关实验(小灯泡标有“2.5V”字样).

  (1)如图甲所示,小丽所接的实验电路存在连接错误,但只需改动一根导线,即可使电路连接正确.请你在应改动的导线上打“×”,并用笔画线代替导线画出正确的接法.

(2)电路连接正确后,闭合开关,发现小灯泡不亮,但电流表有示数.接下来应进行的操作是___________.

    A.更换小灯泡

    B.检查电路是否断路

    C.移动滑动变阻器滑片,观察小灯泡是否发光

   (3)实验过程中,当电压表示数为________V时,小灯泡正常发光,此时电流表的示数如图乙所示,其值为________A,小灯泡的额定功率为_________W.

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29.(4分)为了研究由特殊材料制成的某导体元件L的电学特性,小明和小华通过实验,测得加在该元件两端的电压U与通过它的电流I的实验数据如下表所示:

U/V
0
1
2
3
4
5
I/(×103 A)
0
20
80
180
320
500

   观察表中的实验数据,小明、小华对I与U间的关系提出了以下猜想:

  猜想甲:通过导体元件L的电流可能与加在它两端的电压成正比;

   猜想乙:通过导体元件L的电流可能与加在它两端的电压的平方成正比;

   猜想丙:加在导体元件L两端电压可能与通过它的电流的平方成正比. 

   经分析与论证,你认为,表中的实验数据支持上述哪种猜想?

   答:____________________.

   通过导体元件L的电流I与加在它两端电压U之间的关系式应是:I=_________.

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28.(8分)林刚同学利用如图所示的电路进行实验,当闭合开关S后,发现标有“6V  3W”的灯L1和标有“12V  6W”的灯L2亮度并不相同.已知电源电压为6V,不考虑灯丝电阻值随温度的变化.则:

(1)通过灯泡L1的电流为多大?

(2)灯L1每分钟消耗多少电能? 

(3)灯泡L2的实际功率是多大?电路中灯L1和L2哪个较亮?

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27.(7分)某快艇使用的汽油热值为4.6×107J/kg,密度为0.7×103kg/m3,油箱容积50L,它在水面匀速航行时所受的阻力为1400N.

   (1)如果把油箱装满,则汽油的质量是多少?

   (2)若快艇匀速行驶46km,则牵引力所做的功是多少?

  (3)若快艇匀速行驶46km耗油8L,则发动机的效率为多少?

试题详情

26.(6分)如图甲所示,是2008北京残奥会开幕式最后一棒火炬手侯斌,靠自己双手的力量,攀爬到火炬台底部并最终点燃圣火的照片,该点火仪式充分体现了残疾人自强自立、拼搏向上的勇气和精神.已知他和轮椅总质量为80kg,攀爬高度39m,历时约3min20s,g取10N/kg.

   (1)如果不计机械装置的额外功,求他的平均功率多大?

   (2)小明同学看到火炬手攀爬很费劲,想到物理课上学过利用滑轮组可以省力.小明同学如果站在地面上,用如图乙所示的哪个滑轮组拉起火炬手侯斌最合适,理由是什么?如果该滑轮组机械效率为80%.求小明同学的拉力至少要多大?

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25.(2分)如图所示,“神舟七号”载人飞船完成各项任务后,在返回的过程中,返回舱进入大气层将通过一段黑障区,这一段时间飞船将“烧成”一个大火球,而飞船内的宇航员和设备则安然无恙,下列说法正确的是        (   )

   A.飞船“燃烧”是由于高速运动的飞船与空气摩擦内能转化为机械能

   B.飞船“燃烧”是由于高速运动的飞船与空气摩擦机械能转化为内能

   C.飞船“燃烧”是航天员为了消除太空细菌采取的高温消毒措施

   D.飞船外壳上的烧蚀层先熔化后汽化,从而放出了大量的热量保

    护了飞船

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24.(6分)按照题目要求作图:

   (1)如图甲所示,是一个Z形杠杆,请在图中画出力F对支点O的力臂L.

(2)如图乙所示,用笔画线代替导线将电灯和开关接到电路中.

(3)在图丙中用一个动滑轮和两个定滑轮组成的滑轮组提升重物A,要求作用在绳自由端的拉力方向向下,有三段绳子承担物重,请在图中画出绳的绕法.

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23.如图所示,电源电压恒定.小灯泡L标有“3V  0.6W”字样,

R为定值电阻,闭合S,断开S1,小灯泡正常发光;若再闭合S1

发现电流表示数变化0.3A,则R的阻值为_____,此时灯泡

   L和电阻R消耗的功率之比是_________.

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