2006年全国中学生英语能力竞赛(NEPCS)初赛初二年级组试题
听力部分（共四大题，计30分）
I. 听辨单词 (Words)（共5小题，计5分）
听句子，选出句子中出现的单词。每个句子只读一遍。（答案涂在答题纸上）
1. A. health B. hungry C. helpful D. happy
2. A. climbing B. cooking C. camping D. cleaning
3. A. grass B. glass C. class D. plus
4. A. mouth B. month C. maths D. match
5. A. programme B. problem C. passenger D. policeman
II. 问句应答 (Responses)（共5小题，计5分）
听问句，选出其最佳的应答句。每个句子只读一遍。（答案涂在答题纸上）
6. A. I always go to the zoo on foot on Sunday morning.
B. It's about three miles from the hospital to the zoo.
C. It takes me 20 minutes to find the monkeys at the zoo.
D. I think it is a great idea to go to the zoo together.
7. A. We're going to play football. B. It was very sunny yesterday.
C. My sister is very funny sometimes.
D. I like wearing T-shirts in summer.
8. A. I don't feel well. I have to go to the doctor.
B. Certainly. You can keep them for three weeks.
C. I'm afraid I can't go with you. I'm really busy.
D. I can understand most films in French now.
9. A. Two teaspoons of sugar. B. About 39 metres.
C. For two weeks.
D. Two kilos, please.
10. A. You can take a No. 6 bus. B. It's 020 7303 7019.
C. I can't find my phone.
D. My room number is 1362.
III. 对话理解 (Dialogues)（共10小题，计10分）
A) 听五组小对话，选择描述正确的图片回答问题。每组对话读两遍。（答案涂在答题纸上）
11.Where is the cinema?
12. What will David buy for Lisa's birthday?
13. In which country did Emma enjoy her holiday?
14. How much did the ticket cost?
15. How does the man go to work every day?
B) 听一组长对话，根据其内容选择最佳选项回答下列各题。对话读两遍。（答案涂在答题纸上）
16. Why will Mrs Lee leave on Saturday?
A. She likes to travel on Saturday.
B. She doesn't want to leave late.
C. She is busy on Sunday.
D. Her ticket is for Saturday.
17. When will Mrs Lee arrive in London?
A. At 8:00.
B. At 10:00.
C. At 11:50.
D. At 11:15.
18. Where will Mrs Lee have a meeting after she arrives in London?
A. At a factory.
B. At the airport.
C. At a hotel.
D. At an office.
19. What will Mrs Lee do that evening in London?
A. Meet people in a restaurant.
B. Go to visit the British Museum.
C. Have dinner at a French hotel.
D. Play golf with her friends.
20. How will Mrs Lee go to Paris the next morning?
A. By air.
B. By train.
C. By sea.
D. By bus. IV. 短文理解 (Passages)（共10小题，计10分）
A) 听短文，根据其内容选择最佳选项回答问题。短文读两遍。（答案涂在答题纸上）
21. How many hours does Don work a day?
A. Eight.
B. Seven.
C. Eight and a half.
D. Seven and a half.
22. Don and his workmates get about _________ letters every day.
A. 6,000
B. 60,000
C. 600
D. 60
23. Don feels happy when _________.
A. he watches football matches on TV
B. he helps his wife with the housework
C. he goes out to have dinner with his friends
D. he gives someone a letter from their country
24. What does Don think of his job? He thinks it's _________.
A. boring
B. important
C. easy
D. terrible
25. What doesn't Don like about his job?
A. Getting up too early.
B. Too many letters.
C. Winter days and dogs.
D. Going home late.
B) 非选择题：听短文，根据其内容完成下面的表格。短文读两遍。（答案写在答题纸上）
笔试部分（共七大题，计120分）
I. 选择填空 (Vocabulary and structure) (共20小题，计20分)
A) 选择能够替换划线部分的最佳选项。（答案涂在答题纸上）
31. Finally, he thanked them and went back to his village in the evening.
A. At last
B. Then
C. Next
D. At least
32. Lily is very happy because she is off today.
A. really busy
B. working hard
C. not at work
D. on business
33. This basket is too heavy for me to carry. Could you please give me a hand?
A. look at me
B. help me
C. lend me your basket
D. have a rest
34. Did they have a great time at Ann's birthday party last night?
A. enjoy themselves
B. go on a picnic
C. help themselves
D. have no trouble
35. I have lots of honey but few apples, so give me some apples, please.
A. many
B. much
C. a little
D. a lot
B) 选出下列各题的最佳选项。（答案涂在答题纸上）
36. She began to study English _________ the age of ten and now she can write a letter _________ English.
A. on; at
B. in; on
C. at; for
D. at; in
37. —Did you do well in your _________ history exam?
—Not too bad. I got _________ “B”.
A. / ; an
B. the; a
C. / ; a
D. a; the
38. I like fruit salad very much. Can you tell me how _________ it?
A. bought
B. eating
C. will I have
D. to make
39. —What was the date yesterday?
—It was _________.
A. Wednesday
B. a fine day
C. 4th April
D. a cloudy day
40. The famous writer would like to _________ time in the beautiful countryside.
A. spend
B. cost
C. take
D. pay
41. —Did she play basketball yesterday afternoon?
—No, she _________.
A. goes shopping
B. visited her aunt
C. will stay at home
D. is doing some cleaning
42. _________ people _________ walking along the beach.
A. A small number of; is
B. The number of; are
C. A number of; are
D. The number of; is
43. —It's very late. _________ take a taxi?
—Good idea.
A. Would you like
B. How about
C. What about
D. Why not
44. My Japanese is not very good, so I can _________ understand a Japanese when he speaks too fast.
A. nearly
B. almost
C. hardly
D. ever
45. —When you finish _________ your novel, remember _________ me a call, OK?
—All right.
A. to write; gave
B. writing; to give
C. read; to send
D. reading; giving
C) 情景会话。（答案涂在答题纸上）
46. —What does your cousin look like?
—_________.
—Can he play volleyball?
—Of course.
A. He is a student
B. He likes bananas very much
C. He is tall and thin
D. He went fishing this morning
47. —Dad, I'm not sleeping well these days.
—_________.
—OK, I'll do that.
A. That sounds like a good idea
B. Really? You'd better go to the doctor
C. I really want to win the prize
D. I am glad to hear that
48. —Let's go skating this afternoon.
—_________.
—That's too bad. Maybe another time.
A. I'd like to, but I have a lot of things to do
B. You just need this football
C. The sports car is very expensive
D. Great, skating is my favorite sport
49. —It's chips for lunch. _________?
—Not fish again, please, and we had chicken last night.
—Well, let's have beef and vegetables.
A. How is the weather
B. What would you like with them
C. What time is it
D. How was your holiday
50. —Are you taking the train to Scotland, Wendy?
—No, I'm driving there. It's cheaper.
—_________?
—It takes nine hours to get there on a bus.
A. Why don't you go there by bus
B. Would you please show me your car
C. How long does it take to walk there
D. Would you like to take the train
II. 阅读理解(Reading comprehension)（共20小题，计30分；51—60小题每题1分，61—70小题每题2分）
A
阅读上面的卡片，根据其内容选择最佳答案完成下列各题。（答案涂在答题纸上）
51. _________ license number is B395961136.
A. Michael's
B. Mary's
C. Phyllis'
D. Bob's
52. Mary H. Strenton _________.
A. is a student in America
B. is from the UK
C. was born in 1975
D. lives in Canada
53. Which card shows the card's date of issue?
A. The California Driver's License.
B. The Student Card of University of Texas.
C. The European Identification Card.
D. The Health Insurance Card.
54. What do the four cards have in common?
A. They each show the person's height.
B. Each card has its own number.
C. All of the cards show the person's date of birth.
D. None of the cards show the person's place of birth.
55. Which of the following is TRUE?
A. Phyllis Roth is studying medicine.
B. Michael T. Wright was born in September.
C. Bob Harris was born in Canada.
D. Mary H. Strenton is younger than Michael T. Wright.
B
Last year, I had a great trip to Hearst Castle at San Simeon in California.
Hearst Castle was built by William Randolph Hearst between 1922 and 1939,
at a cost of more than $30 million—about $277 million today.
I spent all day looking around, but a day wasn't enough time to see
everything. There was so much to see. Hearst Castle has four houses. The main
house, “Casa Grande”, is much bigger than the other three, which were used for guests. Many of these guests were Hollywood film stars, and they often came to Hearst's parties.
At Hearst Castle, there are 56 bedrooms, 61 bathrooms and 19 sitting rooms. There are also beautiful gardens, a garage for 25 large cars and two swimming pools, one inside and a larger one outside. I loved the one outside, the “Neptune Pool”—it was a pity we couldn't go swimming!
I found the tour very helpful. The guide told me that Hearst, at the age of ten, toured Europe with his mother, looking at paintings and castles. He never forgot this tour and decided that he wanted his house to look like a castle.
Hearst died in 1951, and his family gave Hearst Castle to the people of California. It is now a museum.
阅读短文，根据其内容对下列句子进行判断。正确的，请选择A；错误的，请选择B；文中没有提及的，请选择C。（答案涂在答题纸上）
56. Hearst Castle at San Simeon in California was cheap to build.
57. Hearst Castle is on a mountain near the sea.
58. Many Hollywood film stars came to Hearst's parties and used the houses there.
59. The swimming pools at Hearst Castle are the same size.
60. After Hearst died in 1951, the Hearst family still lived at Hearst Castle.
C
The polar bear's name in Latin is Ursus maritimus, meaning“sea bear”.
It got this name because it spends most of its time in the Arctic seas.
It is also called by other names, for example, the white bear or the ice
bear. When a polar bear gets out of the sea, it shakes water from its fur
like a dog or it removes the water by rolling on the ice. (61) It is very
cold where polar bears live. The temperature is very often as low as -55℃.
The polar bear is the largest meat-eating animal on land. The male weighs from 350 to 650 kg and he is two and a half to three metres long — almost as long as a car. A polar bear's skin is black but its fur has no colour — it looks white when the sun shines is black but its fur has no colour — it looks white when the sun shines on the ice. It has big feet so it can stand easily on the ice.
The polar bear likes to live alone. It walks long distances, sometimes 30 km a day, because it needs to find food. The bear eats fish and it also enjoys seal meat. It goes swimming or lies in the sun when it isn't looking for food! It is a very good swimmer.
The female bear usually has two babies once every three years. The babies, or cubs, are born in November. Sometimes the cubs die in their first year because they have an accident or they don't get enough food to eat. (62) If they live, they stay with their mother for nearly two years but then they must leave her to go and live alone on the ice.
There are only about 25,000 polar bears alive today. The areas where they live have many problems with pollution, and there are also problems with thin ice. Polar bears need your help!
A）将文中划线的61、62小题的两处句子分别翻译成汉语。（答案写在答题纸上）
B）根据短文内容回答下列各题。（答案写在答题纸上）
63. Why does the polar bear sometimes walk 30 km a day?
64. What problems do the polar bears' living places have?
D
The Eurovision Song Contest takes place in May every year. Before the final
competition, people in each country choose the song they want to represent
（代表） their country.
The idea of the contest is to promote（促进） pop music from all
of the different countries and to give an opportunity to new singers and
composers.
Only members of the European Broadcasting Union can take part in
the competition. Singers do not have to have the nationality of the countries they represent. For example, in 1963 the singer Nana Mouskouri represented Luxembourg, although she is Greek. Since 1986, singers must
be over 16, after a 13-year-old from Belgium won the competition in 1985.
In the first years of Eurovision only the United Kingdom, Ireland, and Malta could sing in English. Now there are no rules about languages, so groups can sing in their own languages, or in English if they want to. Today almost all countries sing in English.
The competition is always in the country where the last year's winner came from. The country with the most winners is Ireland, and many Eurovision singers have become very famous, for example Abba and Julio Iglesias.
阅读短文，根据其内容回答下列各题。（答案写在答题纸上）
65. How old should the Eurovision singers be in 1991?
66. In what language can the Eurovision singers sing now?
67. Which country has the most Eurovision winners?
E
阅读上面的目录，根据其内容完成下列各句，每空一词。（答案写在答题纸上）
68. This book gives readers information about travelling in _________ and it has four _________ and more than 233 pages.
69. If you want to know the _________ _________, you can turn to Page 184.
70. You can find something about _________ in Chapter 7 and if you are interested in shopping, you can read Chapter _________.
III. 完形填空(Cloze)(共20小题，计20分)
A) 阅读短文，根据其内容用括号内所给动词的适当形式填空。（答案写在答题纸上）
Mr Anderson works as a headmaster in a middle school. His father (71)_________ (have)
a factory in a town and makes a lot of money. Mr Anderson's father loves his son very
much and gives his son everything he wants. However, Mr Anderson keeps (72)_________
(try) to save everything he can.
One summer it was raining hard for a long time and many people (73)_________
(lose) their houses and farms during a flood. The government asked people to help those
who (74)_________ (be) in trouble. As a headmaster, Mr Anderson told the whole school
(75)_________(collect) money for the people who had lost their homes.
“Each of us should (76)_________ (help) the farmers who are in trouble after the flood,” he said at a school meeting.
Mr Anderson's speech moved all the teachers and the students. They (77) _________ (do) their best to help the hungry people with money and goods. Mr Anderson was very pleased with the result.
As soon as he (78)_________ (get) home that afternoon, his little son asked Mr Anderson to buy him a new motorbike. The little boy had given his old one to the people in need.
“How dare you do that?” Mr Anderson said angrily.
“You told us to collect money this morning, (79)_________ (not, do) you?”
“Yes, I did,” (80)_________ (say) the father. “But I was asking for other children, not for you!”
B) 阅读短文，根据其上下文语境提示，用方框中所给单词或短语的适当形式填空，每个只可用一次。其中有5个多余。（答案写在答题纸上）
I roll my giant, juicy, (81)_________ watermelon out the back door
to our picnic table. Mum brings a (82)_________ and some paper plates.
My sister follows her.
“Oh,(83)_________,”she says. “I want some.”
“(84)_________,” I tell her. “I'm going to eat it all by
myself.”
“Mum!” she complains.
“Your sister saved her money and (85)_________ it herself. She decides what to do with it.”
My brother comes out next.
“Oh, watermelon,” he says, “Can I have some?”
“No way,”I tell him. “I'm going to eat it all by myself.”
“Mum!” my brother (86)_________.
“It's your sister's watermelon. She decides.”
“You can't eat that all (87)_________,” he says.
“Yes, I (88)_________!”
Mum cuts the watermelon into four (89)_________, and then cuts each of those in half. Eight pieces total.
I reach for my first piece and take a bite. Red juice runs down my chin (下巴).
My father comes (90)_________. “Oh, watermelon!” he says, seeing it.
“Don't even ask,” says my brother.
“She won't share,” my sister adds.
IV. 句式转换 (Sentence pattern transf to the swimming club?
92. There were some sharks in the aquarium. （改为否定句）
There _________ _________ sharks in the aquarium.
93. Jack can't go shopping because he has to help his mother with the housework. （对划线部分提问）
_________ _________ Jack go shopping?
94. What time does Maria read English books after supper every day? （用the day before yesterday 改写句子）
What time _________ Maria _________ English books after supper the day before yesterday?
95. Those children need the man's advice and help. （改为一般疑问句）
_________ those children _________ the man's advice and help?
B) 根据上句改写下句，使两句意思相同或相近。每空一词。（答案写在答题纸上）
96. Which city do you like best?
What is your _________ _________?
97. To get from this village to that one usually takes 30 minutes.
_________ usually _________ 30 minutes to get from this village to that one.
98. Bruce has breakfast quickly every day.
Bruce has a _________ _________ every day.
99. Bob is fifteen years old, and Paul is fifteen years old, too.
Bob is _________ old _________ Paul.
100. The boy didn't go to the zoo last weekend because he had a sore back.
The boy didn't go to the zoo last weekend _________ _________ his sore back. V. 翻译(Translation)（共5小题，计10分）
根据提示，将下列汉语句子翻译成英语。（答案写在答题纸上）
101. 请往牛奶里加些糖。（add...to）
________________________________________
102. 我将一直在这儿等到下午两点钟。（until）
________________________________________
103. 我认为一个好朋友能让我开心。（make sb happy）
________________________________________
104. 如果你头痛得厉害，就应该早点上床睡觉。（have a bad headache）
________________________________________
105. 明天别忘了把我的那本书带回来。（forget）
________________________________________
VI. 智力测试(IQ)（共5小题，计5分）
回答下列问题。（答案写在答题纸上）
106. Which number should replace （替代）the“?”?
1, 3, 4, 7, 11, 18, 29, ?
107. Rearrange （重新排列） the letters on each page of this diary to find six days of the week. Which day is missing?
第27届全国中学生物理竞赛复赛试卷本卷共九题，满分160分．计算题的解答应写出必要的文字说明、方程式和重要的演算步骤．只写出最后结果的不能得分．有数字计算的题．答案中必须明确写出数值和单位．填空题把答案填在题中的横线上，只要给出结果，不需写出求解的过程． 一、（15分）蛇形摆是一个用于演示单摆周 期与摆长关系的实验仪器（见图）．若干个摆球位于同一高度并等间距地排成一条直线，它们的悬挂点在不同的高度上，摆长依次减小．设重力加速度g=9.80 m/s2, 1．试设计一个包含十个单摆的蛇形摆（即求出每个摆的摆长），要求满足：(a）每个摆的摆长不小于0.450m，不大于1.00m;(b）初始时将所有摆球由平衡点沿x轴正方向移动相同的一个小位移xo(xo<<0.45m)，然后同时释放，经过40s后，所有的摆能够同时回到初始状态． 2．在上述情形中，从所有的摆球开始摆动起，到它们的速率首次全部为零所经过的时间为________________________________________. 二、（20分）距离我们为L处有一恒星，其质量为M，观测发现其位置呈周期性摆动，周期为T，摆动范围的最大张角为△θ．假设该星体的周期性摆动是由于有一颗围绕它作圆周运动的行星引起的，试给出这颗行星的质量m所满足的方程．若L=10光年，T=10年，△θ=3毫角秒，M=Ms（Ms为太阳质量），则此行星的质量和它运动的轨道半径r各为多少？分别用太阳质量Ms和国际单位AU（平均日地距离）作为单位，只保留一位有效数字．已知1毫角秒=角秒，1角秒=度，1AU=1.5×108km,光速c=3.0×105km/s.
2018年全国初中学生化学素质和实验能力竞赛 （第十八届天原杯）复赛试题 试题说明：1.本试卷共8页，满分100分。（附加题供选用） 2.可能用到的相对原子质量： H:1 C:12 N:14 O:16 F:19 Na:23 Al:27 S:32 Cl:35.5 K:39 Ca:40 Mn:55 Fe:56 Cu:64 Zn:65 Ba:137 3.考试时间：2小时 一、选择题(本题包括15个小题，每小题2分，共30分。每小 题有1个或2个选项符合题意。若有两个答案的错1个不得分， 1．2018年10月24日，我国使用“长征三号甲”运载火箭将“嫦娥1号”送上月球轨道，其任务之一是探测月球上氦–3（质子数为2， 中子数为1的原子）资源。下列氦–3原子的原子结构示意图中正确的是（ ） 2．第29届奥林匹克运动会将于2018年8月8日在北京举行。下列措施不符合绿色奥运理念的是（ ） A ．奥运场馆周围的路灯采用太阳能光伏发电技术 B ．在奥运场地使用电动汽车和新型清洁燃料汽车 C ．场馆附近的绿化采用微灌或滴灌智能控制技术 D ．将奥运村的生活垃圾全部集中深埋 3．1991年碳纳米管被发现。碳纳米管是由石墨中的碳原子层卷曲而成的管状的材料，管的直径一般为几纳米到几十纳米，管的厚度仅为几纳米。碳纳米管由于其独有的结构和奇特的物理、化学特性以及潜在的应用前景而受到人们的关注。下列有关碳纳米管的说法中正确的是（ ） A ．碳纳米管是一种新型的高分子化合物 B ．碳纳米管的化学性质常温时很稳定 C ．碳纳米管导电属于化学变化 D ．碳纳米管的结构和性质与金刚石均相同 4．闪电时空气中有臭氧（O 3）生成。下列说法中正确的是（ ） A ．O 3和O 2混合得到的是纯净物 B ．O 2比O 3稳定 C ．等质量的O 3和O 2含有的氧原子数之比是2︰3 D ．O 3与O 2的相互转化是物理变化
驻马店市第十九中学八年级英语竞赛试题 一、听力理解（20小题，每小题 1 分，共20分） 第一节听下面 5 段对话。每段对话后有一个小题，从题中所给的 A..B.C 三个选项中选出最佳答案，并将其标号填入题前括号内。每段对话读两遍。 （） 1.What will the man do later? A. Have breakfast. B. Run . C. Watch TV （） 2.What does the man advise the woman to do? A. To write an e-mail to Mike. B. To give Mike a present. C. To see a movie with Mike. （） 3.Where does the woman want to go? A. To the park. B.To the supermarket. C. To the cinema. （） 4.Where did the man go last weekend? A. To the US. B. To Canada. C. To England （） 5.What's the matter with Tom? A. He has a stomachache. B. He has a fever. C. He has headache. 第二节听下面几段对话或独白。每段对话或独白后有几个小题，从题中所给的 A.B.C 三个选项中选出最佳答案，并将其标号填入题前括号内。每段对话或独白读两遍。 听下面一段对话，回答第6至第7两个小题. （） 6.How does the man go to work now? A. By car B. By subway C. On foot （）7.How long has the man had the car? A .For four years B. For five years C. For six years 听下面一段对话，回答第8 至第10 三个小题。 （）8.What does Mom expect Frank and his sister to do? A. To do housework B.To work hard. C. To take exercise. （）9.What does Frank's sister often do? A.She often sweeps the floor. B. She often folds the clothes. C She often does the dishes.. （）10.How often does Frank clean his room? A.Twice a month. B. Twice a week. C.Once a week 听下面一段独白，回答第11至第12两个小题。 （）11.How long has it rained in the city? A. For two days. B. For three days. C.For four days. （）12.When will the rainstrom come probably? A.On Friday B. On Saturday C. On Sunday 听下面一段对话，回答第13 至第15三个小 题。 （）13.How many pandas are there? A. Two B. Three C.Five （）14. What does the man think of pandas? https://www.doczj.com/doc/7a12340922.html,zy B. Cute C.Active （）15.What does the woman want to do? A.To feed the pandas. B. To take photos C. To play with the pandas.
2012年全国高中数学联赛模拟试题二 一、选择题：每题6分，满分36分 1、数列10021,,,x x x 满足如下条件：对于k x k ,100,2,1 =比其余99个数的和小k ，已知 n m x = 50，m ，n 是互质的正整数，则m+n 等于（ ） A 50 B 100 C 165 D 173 2、若2 6cos cos ,22sin sin = +=+y x y x ，则)sin(y x +等于（ ） A 2 2 B 2 3 C 2 6 D 1 3、P 为椭圆 19 162 2 =+y x 在第一象限上的动点，过点P 引圆92 2 =+y x 的两条切线PA 、PB ，切点分 别为A 、B ，直线AB 与x 轴、y 轴分别交于点M 、N ，则MON S ?的最小值为（ ） A 2 9 B 32 9 C 4 27 D 34 27 4．函数2 0.3()log (2)f x x x =+-的单调递增区间是（ ） . (A) (,2)-∞- (B) (,1)-∞ (C) (-2,1) (D) (1,) +∞ 5．已知,x y 均为正实数，则22x y x y x y + ++的最大值为（ ） . (A) 2 (B) 23 (C) 4 (D) 43 6．直线y=5与1y =-在区间40, πω????? ? 上截曲线 sin (0, 0)2y m x n m n ω =+>>所得的弦长相等且不为零，则下列描述正确的是（ ） . （A ）35,n= 2 2 m ≤ （B ）3,2m n ≤= （C ）35,n=2 2 m > （D ）3,2m n >= 二、填空题：每小题9分，满分54分 7、函数)(x f 满足：对任意实数x,y ，都有 23 ) ()()(++=-y x xy f y f x f ，则=)36(f . 8、正四面体ABCD 的体积为1，O 为为其中心. 正四面体D C B A ''''与正四面体ABCD 关于点O 对 称，则这两个正四面体的公共部分的体积为 . 9、在双曲线xy ＝1上，横坐标为 1 +n n 的点为n A ，横坐标为 n n 1+的点为)(+∈N n B n .记坐标为 （1，1）的点为M ，),(n n n y x P 是三角形M B A n n 的外心，则=+++10021x x x . 10．已知sin(sin )cos(cos )x x x x +=-，[]0,,x π∈ 则=x . 11．设,A B 为抛物线2 2(0)y px p =>上相异两点，则2 2 O A O B AB +- 的最小值为 ___________________． 12．已知A B C ?中，G 是重心，三内角,,A B C 的对边分别为,,a b c ，且
第26届全国中学生物理竞赛复赛试卷 一、填空（问答）题（每题5分，共25分） 1．有人设想了一种静电场：电场的方向都垂直于纸面并指向纸里，电场强度的大小自左向右逐渐增大，如图所示。这种分布的静电场是否可能存在？试述理由。 2．海尔-波普彗星轨道是长轴非常大的椭圆，近日点到太阳中心的距离为0.914天文单位（1天文单位等于地日间的平均距离），则其近日点速率的上限与地球公转（轨道可视为圆周）速率之比约为（保留2位有效数字） 。 3．用测电笔接触市电相线，即使赤脚站在地上也不会触电，原因是 ；另一方面，即使穿绝缘性能良好的电工鞋操作，测电笔仍会发亮，原因是 。 4．在图示的复杂网络中，所有电源的电动势均为E 0，所有电阻器的电阻值均为R 0，所有电容器的电容均为C 0，则图示电容器A 极板上的电荷量为 。 5．如图，给静止在水平粗糙地面上的木块一初速度，使之开始运动。一学生利用角动量定理来考察此木块以后的运动过程：“把参考点设于如图所示的地面上一点O ，此时摩擦力f 的力矩为0， 从而地面木块的角动量将守恒，这样木块将不减速而作匀速运动。”请指出上述推理的错误，并给出正确的解释： 。 二、（20分） 图示正方形轻质刚性水平桌面由四条完全相同的轻质细桌腿1、2、3、4支撑于桌角A 、B 、C 、D 处，桌腿竖直立在水平粗糙刚性地面上。已知桌腿受力后将产生弹性微小形变。现于桌面中心点O 至角A 的连线OA 上某点P 施加一竖直向下的力F ，令 c OA OP ，求桌面对桌腿1的压力F 1。
三、（15分） 1．一质量为m 的小球与一劲度系数为k 的弹簧相连组成一体系，置于光滑水平桌面上，弹簧的另一端与固定墙面相连，小球做一维自由振动。试问在一沿此弹簧长度方向以速度u 作匀速运动的参考系里观察，此体系的机械能是否守恒，并说明理由。 。 2．若不考虑太阳和其他星体的作用，则地球-月球系统可看成孤立系统。若把地球和月球都看作是质量均匀分布的球体，它们的质量分别为M 和m ，月心-地心间的距离为R ，万有引力恒量为G 。学生甲以地心为参考系，利用牛顿第二定律和万有引力定律，得到月球相对于地心参考系的加速度为2R M G a m =；学生乙以月心为参考系，同样利用牛顿第二定律和万有引力定律，得到地球相对于月心参考系的加速度为 2R m G a e =。这二位学生求出的地-月间的相对加速度明显矛盾，请指出其中的错误，并分别以地心参考系（以地心速度作平动的参考系）和月心参考系（以月心速度作平动的参考系）求出正确结果。 四、（20分）火箭通过高速喷射燃气产生推力。设温度T 1、压强p 1的炽热高压气体在燃烧室内源源不断生成，并通过管道由狭窄的喷气口排入气压p 2的环境。假设燃气可视为理想气体，其摩尔质量为μ，每摩尔燃气的内能为u =c V T （c V 是常量，T 为燃气的绝对温度）。在快速流动过程中，对管道内任意处的两个非常靠近的横截面间的气体，可以认为它与周围没有热交换，但其内部则达到平衡状态，且有均匀的压强p 、温度T 和密度ρ，它们的数值随着流动而不断变化，并满足绝热方程C pV V V c R c =+（恒量） ，式中R 为普适气体常量，求喷气口处气体的温度与相对火箭的喷射速率。
2013年全国初中学生化学素质和实验能力竞赛(第23届天原杯)复赛试题 可能用到的相对原子质量:H-1 C-12N-14 O-16 Na-23 Mg-24 Al-27 S-32 Cl-35.5 K-39 Mn-55 Fe-56 Cu-64 Zn-65 Ag-108 Sn-119 Hg-201 Pb-207 一、选择题(每小题2分,共30分,有1个或2个选项符合题意) 1、2013年世界地球日的主题是"多样的物种,唯一的地球,共同的未来".下列描述符合这一主题的是( ) A.为粮食增产,多施高效化肥、农药 B.霾是一种自然现象,对人体健康影响不大 C.大力推广新型材料 D.努力实施绿色化学,把化学对环境的负面影响减少到最低 2、化学概念相互间存在如下3种关系,下列对概念间关系的说法正确的是( ) A.纯净物与混合物属于包含关系 B.化合物与氧化物属于包含关系 C.单质与化合物属于交叉关系 D.氧化反应与化合关系属于并列关系 3、过氧化氢是常见的过氧化物,下列物质也属于过氧化物的是( ) A.MnO 2 B.CaO 2 C.NO 2 D.SiO 2 4、晋代葛洪的《食肉方》(去除黑痣的药方)中记载:"取白炭灰(石灰)、 荻灰(草木灰)等分煎合……"可去黑痣.起到食肉作用的主要物质是( ) A.碳酸钙 B.熟石灰 C.碳酸钾D.苛性钾 5、生物体死亡后,体内含有的碳-14会逐渐减少,(称为衰变)因此科学家可通过测量生物体遗骸中碳-14的含量,来计算它存活的年代,这种方法称之为放射性碳测年法.碳-14原子核中含6个质子与8个中子,在衰变时,一个中子变成质子,形成新的原子核.下列关于新原子核的说法正确的是( )A.碳原子核,含7个质子,8个中子 B.氮原子核,含7个质子,7个中子 C.碳原子核,含6个质子,7个中子 D.氧原子核,含7个质子,8个中子 6、取4份等质量的KClO 3,向其中3份中分别加入少量等质量的KMnO 4、MnO 2和Mn,分别在某温度下加热至质量不再改变,测定产生的氧气的质量.然后,将剩余固体溶于足量水中,添加过物质的组别中均有相同组成的不同物.测定结果如下: 已知m1＞m2＞m3,下列关于此实验的说法一定正确的是( ) A.3种物质的加入都有利于KClO 3分解制氧气 B.残留不溶物的质量关系为m1＜m2＜m3 C.KMnO 4是KClO 3分解制氧气效果最好的催化剂 D.不加入其它物质时,KClO 3未发生分解反应 7、下列各组微粒中,属于同一种元素的是( ) 8、下列变化过程一定发生化学反应的是( )A.燃烧 B.爆炸 C.颜色发生了改变 D.状态发生了改变 9.将硅粉与镁粉混合后隔绝空气强热,得到一种暗蓝色的化合物.将此化合物投入水中,发生剧烈反应,产生气体,并伴有爆炸声与火光.此过程不可能发生的反应是( )A. B. C. D. 10、甲、乙两种固体物质的溶解度如图1所示.常温下,分别向装有适量甲、乙物质的两支试管中加入等量的蒸馏水,充分振荡后,两支试管底部都均有未溶解的固体;再将两支试管放入盛有冰水混合物的烧杯里,如图2所示.关于该实验,下列说法正确的是( ) A.乙溶液中溶质的质量分数增大 B.装有甲物质的试管中剩余的固体减少 C.甲、乙两物质的溶解度都增大 D.两支试管里剩余的固体都增多 11、如上右图下列CO 2的制备装置中,不能起到"随开随用,随关随停"效果的是 12、某同学想要知道10g 食盐的体积,他应该采用的方法是( ) A.将食盐放入空量筒中,观察表面对应刻度的变化 B.将食盐放入装有水的量筒中,观察液面对应刻度的变化 C.将食盐放入装有沙子的量筒中,观察表面对应刻度的变化 D.将食盐放入装有饱和食盐水的量筒中,观察液面对应刻度的变化 13、3种无色溶液,溶质分别为硫酸铵、氯化钠和碳酸钾.3位同学设计的鉴定方案如下: 甲:各加入少量盐酸,有气体产生的是碳酸钾.然后向明显现象的试管中滴加少量氯化钡溶液,有沉淀产生的是硫酸铵,无沉淀产生的是氯化钠 乙:各加入足量烧碱溶液,加热,的气体产生的是硫酸铵.然后向明显现象的试管中滴加少量硝酸银溶液,再加入少量稀硝酸,有沉淀产生的是氯化钠,无沉淀产生的是碳酸钾 丙:各加入少量氯化钡溶液,再加入少量稀硝酸,有沉淀产生的是硫酸铵,然后向明显现象的试管中滴加少量硝酸银溶液,有沉淀产生的是氯化钠,无沉淀产生的是碳酸钾 A.只有甲 B.甲和乙 C.乙和丙 D.甲和丙 14、现有失去标签的氯化钙、硝酸银、盐酸、碳酸钠4种无色溶液.将它们编号为甲、乙、丙、丁后,两两混合的现象如下表所示.根据实验现象判断甲溶液中的溶质的化学式是( ) A.CaCl 2 B.AgNO 3 C.HCl D.Na 2CO 3 15、将5.4g 金属铝投入一定量的混合盐溶液中,反应后可得到36.0g 金属单质(无气体产生).则原混合盐的组成可能为: ( ) A.Pb(NO 3)与2Hg(NO 3)2 B.Fe(NO 3)2和Zn(NO 3)2 C.AgNO 3与Cu(NO 3)2 D.Sn(NO 3)2与Mg(NO 3)2 二、填空题 16、(4分)生活与化学密切相关,处处充满着化学知识. (1)下列食物中,能提供大量维生素的是( )(填标号)A.牛奶 B.大米 C.蔬菜 (2)加钙牛奶中的钙是指钙元素,身体中一旦缺钙,可能患有的疾病是( )(填"骨质疏松"或"贫血") (3)下列物品中,所使用的主要材料属于天然纤维的是( )(填标号)A.橡胶手套B.棉布围裙 C.塑料保鲜膜 (4)我们常用洗涤剂清洗餐具上的油污,这是因为洗涤剂具有( )功能. 17、(6分)我们周围的物质世界是由100多种元素组成,为了便于研究元素的性质,常常需要寻找它们之间的内在规律.下表列出的是1-18号元素的部分最高正化合价和最低负化合价.请阅读并回答下列问题: (1)11号元素属于( )元素(填"金属"或"非金属"),它在化学反应中形成的离子与( )(填元素符号)原子具有相同的核外电子排布. (2)16号元素的原子核外电子数为( )推测该元素最低负化合价为( )最高正化合价的氧化物的化学式为( ) (3)从化合价角度分析,我们可以发现一些规律.请写出其中的一个: 18、某厂废水中含有质量分数为4.9%的H 2SO 4,需要中和后才能排放.某兴趣小组同学经过讨论,提出了两种中和方案,所用试剂的价格如下 : (1)请从经济与产物角度说明选择氢氧化钙的理由: ① ② (2)有同学建议用氨水进行中和,可以回收一种化肥,其化学式为 .该废水还会引起的环境问题是( )(填标号) A.重金属污染 B.有毒物质污染 C.富营养化污染D.悬浮物污染 19、(5分)一包白色粉末,由CuSO 4、CaCO 3、Na 2SO 4、NaOH 中的两种或两种以上的物质混合组成.为探究其组成,进行如下实验: (1)取少量白色粉末,向其中加入足量的水,充分搅拌后过滤,得到白色沉淀和无色滤液,则原白色粉末中一定不含有 (2)取实验(1)滤出的白色沉淀,向其中加入足量的盐酸,沉淀全部溶解,并产生无色气体 则原白色粉末中一定含有 根据上述实验可推断:原白色粉末的组成有( )种可能 为进一步探究原白色粉末的组成,取实验(1)得到的滤液,向其中通入CO 2,产生白色沉淀,则可推断原白色粉末中一定还含有 20、(3分)高氯酸(HClO 4)是最强酸,现有一种不常见的氯的化合物叫做高氯酸氯,其分子中氯的质量分数为0.526,且每个分子中含有4个氧原子.(1)高氯酸氯的化学式为( ) (2)高氯酸氯在室温下即发生分解,形成Cl 2、O 2和另一种氯的氧化物.已知该反应的化学方程式中3种产物的化学计量数相同,写出该分解反应的化学方程式: 21、(6分)FentOn 法常用于处理含难降解有机物的工业废水.其原理是利用Fe2+和H 2O 2的反应产生降解污染物的活性成分,现运用该方法降解有机污染物p-CP,探究有关因素对降解反应速率的影响.实验探究:控制p-CP 的初始浓度相同,实验温度恒定在25℃或40℃(其余实验条件见下表),设计如下对比试验: (1)请完成以下实验设计表(表中不要留空格) (2)实验①、②表明温度升高,降解反应速率 实验发现,温度过高时,降解反应较难发生.请从FentOn 法所用试剂H 2O 2的角度分析原因: (3)实验③得出的结论是:pH 等于10时,
监利县廖池中学 2009－20XX年度（下）八年级英语竞赛试卷满分100分。时间100分钟。请将答案填写到第二卷上，考生只交第二卷。 I、单项填空（15分） 1. There _____ a football match on TV this afternoon. A. is going to have B. will be C. is going to play D. will play 2. Travelling by train is ____ cheaper and _____ enjoyable than by air. A. very, very much B. quite, much too C. more, much more D. much, far more 3. He explained ____ how to get there. A. to me B. for me C. me D. with me 4. It’s great fun ____ a pet dog at home. A. to keep B. to take C. keep D. find 5. How long ____ you both ___ love? A. are, with B. do, fall in C. are, in D. are , fall in 6. It _____ that his father knew about it. A. seems B. seems to C. seemed D. seemed to 7. You forgot ____ the door. Oh, _____ , I’ll go and close it. A. closing, so did I B. to close, so I did C. closing, nor did I D.to close, neither did I 8. He ____ by bike to school, but now he walks. A. used to going B. is used to going C. used to go D. is used to go 9. Look at this photo. Can you ___ her name? A. think over B. think of C. think about D. thinking of 10.All the students were sweeping the floor ___ they head a man ___ “help”. A. when, shouting B. white , to shout C. when, to shout D. while, shouts 11. Jimmy is leaving for a holiday. Really? Where ___ he ____? A. has, gone B. will, go C. did, go D. does, go 12.Would you mind my opening the window? ____. A. Yes, I would B. Sorry, I wouldn’t C. No, not at all D. No, please don’t 13.Why don’t you get him some junk food? ______. A. That’s not healthy enough B. That’s too healthy C. That’s delicious food D. That’s enough healthy 14.What can you catch but can’t throw. A. a girl B. a boy C. a dog D. a cold 15.Fill in the following blanks with only one word. ____ is greater than God. A. Everything B. Nothing C. Something D. Anything II.完形填空（10分） Henry was not good at maths . Even when the teacher explained something a second time, he still could not _16_ it. “Never mind, I’ll sit next to the boy who’s the best at _17_” Henry thought, “and 18 his answers”. The day of the exam came, and Henry sat next to Allan, who was 19 at the top of the class in maths. Henry carefully copied Allan’s answers onto his own exam paper. At he end of the exam, the teacher said, “Well, boys and girls, I’ve decided to give a red star to the students who got the highest grades. It’s 20 for me to decide who to give the star to, however, 21 two students, Henry andAllan, got the 22 grade” After a moment she went on: “But I’ve decided to give the star to 23 this time”. Henry was 24 when he heard this. He stood up and said: “But I got the same grade as Allan, madam”
高中化学竞赛初赛模拟试卷（02）（时间：3小时满分：100分） 题号 1 2 3 4 5 6 7 8 9 10 满分 H 1.008 相对原子质量He 4.003 Li 6.941 Be 9.012 B 10.81 C 12.01 N 14.01 O 16.00 F 19.00 Ne 20.18 Na 22.99 Mg 24.31 Al 26.98 Si 28.09 P 30.97 S 32.07 Cl 35.45 Ar 39.95 K 39.10 Ca 40.08 Sc 44.96 Ti 47.88 V 50.94 Cr 52.00 Mn 54.94 Fe 55.85 Co 58.93 Ni 58.69 Cu 63.55 Zn 65.39 Ga 69.72 Ge 72.61 As 74.92 Se 78.96 Br 79.90 Kr 83.80 Rb 85.47 Sr 87.62 Y 88.91 Zr 91.22 Nb 92.91 Mo 95.94 Tc [98] Ru 101.1 Rh 102.9 Pd 106.4 Ag 107.9 Cd 112.4 In 114.8 Sn 118.7 Sb 121.8 Te 127.6 I 126.9 Xe 131.3 Cs 132.9 Ba 137.3 La－ Lu Hf 178.5 Ta 180.9 W 183.8 Re 186.2 Os 190.2 Ir 192.2 Pt 195.1 Au 197.0 Hg 200.6 Tl 204.4 Pb 207.2 Bi 209.0 Po [210] At [210] Rn [222] Fr [223] Ra [226] Ac－ La Rf Db Sg Bh Hs Mt Ds La系 La 138.9 Ce 140.1 Pr 140.9 Nd 144.2 Pm 144.9 Sm 150.4 Eu 152.0 Gd 157.3 Tb 158.9 Dy 162.5 Ho 164.9 Er 167.3 Tm 168.9 Tb 173.0 Lu 175.0 第一题（4分） 1．下列物质中，可溶于水的是 A 胆固醇： B 芬必得： C 维生素C： D 保幼激素JH-I： 2．信息、材料和能源被称为新科技革命的三大支柱。下列有关说法错误的是 A 在即将到来的新能源时代，核能、太阳能、氢能将成为主要能源 B 目前中美日等国掌握的陶瓷发动机技术，大大提高了发动机的能量转化效率 C 2002年12月30日发射成功的“神州四号”使用了大量的复合材料 D 法国已经掌握了核燃料的循环使用，并应用在各核电站中 3．下列热化学方程式中△H的绝对值能表示可燃物的燃烧热的是 A CH4（g）＋2O2（g）＝CO2（g）＋2H2O（g）；△H＝－802.3kJ/mol B H2（g）＋Cl2（g）＝2KCl（g）；△H＝－184.6kJ/mol C 2H2（g）＋O2（g）＝2H2O（l）；△H＝－571.6kJ/mol D CO（g）＋1/2O2（g）＝CO2（g）；△H＝－283kJ/mol 4．右图为一种冰的晶胞，请问该每个晶胞中有几个氢键 A 2 B 4 C 8 D 12
2016全国初中物理竞赛复赛试题(含答案） 初中物理是义务教育的基础学科，一般从初二开始开设这门课程，教学时间为两年。一般也是中考的必考科目。随着新高考/新中考改革，学生的综合能力越来越重要，录取方式也越来越多，三位一体录取方式十分看重学生的课外奖项获取。万朋教育小编为初中生们整理了2016年全国初中物理竞赛试卷和答案，希望对您有所帮助。 第29届全国中学生物理竞赛复赛试卷 本卷共8题，满分160分。 一、（17分）设有一湖水足够深的咸水湖，湖面宽阔而平静，初始时将一体积很小的匀质正立方体物块在湖面上由静止开始释放，释放时物块的下底面和湖水表面恰好相接触。已知湖水密度为ρ；物块边长为b ，密度为'ρ，且ρρ<'。在只考虑物块受重力和液体浮力作用的情况下，求物块从初始位置出发往返一次所需的时间。 解： 由于湖面足够宽阔而物块体积很小，所以湖面的绝对高度在物块运动过程中始终保持不变，因此，可选湖面为坐标原点并以竖直向下方向为正方向 建立坐标系，以下简称x 系. 设物块下底面的坐标为x ，在物块未完全浸没入湖水时，其所受到的浮力为 2b f b x g ρ= ( x b ≤) (1) 式中 g 为重力加速度.物块的重力为 3 g f b g ρ'= (2) 设物块的加速度为a ，根据牛顿第二定律有
3 g b b a f f ρ'=- (3) 将(1)和(2)式代入(3)式得 g a x b b ρρρρ'?? =- - ?'? ? (4) 将x 系坐标原点向下移动/b ρρ' 而建立新坐标系，简称X 系. 新旧坐标的关 系为 X x b ρρ ' =- (5) 把(5)式代入(4)式得 g a X b ρρ=-' (6) (6)式表示物块的运动是简谐振动. 若0X =，则0a =，对应于物块的平衡位置. 由(5)式可知，当物块处于平衡位置时，物块下底面在x 系中的坐标为 0x b ρρ ' = (7) 物块运动方程在 X 系中可写为 ()()cos X t A t ω?=+ (8) 利用参考圆可将其振动速度表示为 ()()sin V t A t ωω?=-+ (9) 式中ω为振动的圆频率 'g b ρωρ= (10) 在(8)和(9)式中 A 和?分别是振幅和初相位，由初始条件决定. 在物块刚被释 放时，即0t =时刻有x =0，由(5)式得
2016年上海市初中学生化学竞赛（第二十八届天原杯）复赛试题 （总分120分，时间120分钟） 相对原子质量：H-1 Li-7 C-12 N-14 O-16 Fe-56 一、选择题（本题包括16个小题，共40分，每小题有1个或2个选项符合题意。若有两个答案的错1个不得分，漏选1个扣一半分数） 1、2015年10月，因发现抗疟疾药青蒿素而首获诺贝尔自然科学类奖的中国本土科学家是 A. B. C. D. 2、化学用语书写正确的是 A、金钢石 B、汞蒸汽 C、氯化氨 D、瓷坩埚 3、已知HClO与H2SO3都是弱酸，两者可以发生反应：HClO + H2SO3→ HCl + H2SO4，下列判断合理的是 A、该反应属于复分解反应 B、该反应中H2SO3作还原剂 C、该反应说明某些酸具有一定的碱性 D、反应后溶液pH>7 4、垃圾应分类收集，以下物质应放置于贴有“”标志垃圾筒内的是 A、废电池 B、旧报纸 C、空易拉罐 D、过期药品 5、在命名化学物质时，如果某元素的化合价不止一种，一般我们把其中比较稳定而且常见的化合价作为标准，化合价比它高的加上前缀“高”，化合价比它低的加上前缀“亚”，以此进行区分。据此，下列物质命名正确的是 A、BaMnO4：锰酸钡 B、Na2FeO4：铁酸钠 C、Hg2Cl2：氯化汞 D、CaHPO4：亚磷酸氢钙 6、波尔多液是一种含铜杀菌剂，制作波尔多液的主要原料除了水和硫酸铜外，还需 A、纯碱 B、烧碱 C、硫磺 D、生石灰 7、下列能制备氢气并能灌充小氢气球的实验装置是
A. B. C. D. 8、在设计探究实验时，往往保持所有条件均相同进行多次实验，其目的是 A、增加数据数量，便于总结数据变化规律 B、控制实验条件进行对比 C、消除试剂中所含杂质对实验结果的干扰 D、消除偶然的不确定因素带来的误差 9、已知酸碱中和反应放出的热量与消耗的酸、碱的物质的量成正比。将30mL某稀硫酸与30mL某氢氧化钠溶液混合，恰好完全反应，溶液温度升高△T1，保持两种溶液浓度不变，体积均改为90mL进行中和，溶液温度升高△T2，若不计热量损失，△T1与△T2的关系是 A、△T1=△T2 B、△T1=3△T2 C、3△T1=△T2 D、6△T1 =△T2 10、某溶液的溶质可能是K2SO4、KCl、Na2CO3、NaOH中的一种或几种，某同学取4份此溶液样品，分别进行如下实验： ①进行焰色测试，火焰呈黄色，透过蓝色钴玻璃可以看到火焰呈紫色 ②加入硝酸银，产生白色沉淀，再加入稀硝酸，沉淀部分溶解，产生气体 ③加入足量氯化钡溶液，产生白色沉淀，该沉淀部分溶于稀硝酸且放出气体 ④加入足量硝酸钡溶液，产生白色沉淀，过滤后向滤液中加入硝酸银溶液，产生白色沉淀该同学最终确定该溶液中仅存在K2SO4、KCl、Na2CO3三种溶质。请分析．该同学只需完成上述哪两个实验，即可得出此结论？ A、①② B、③④ C、②③ D、②④ 11、意大利化学家阿伏伽德罗在化学上的重大贡献是建立分子学说，他提出：同温同压下，相同体积的任何气体含有相同数目的分子。现有两个密闭容器，分别装有等质量的甲、乙两种气体，若两容器内气体的温度和压强均相同，且甲的密度大于乙的密度。下列说法正确的是
初二英语竞赛试题(3) 初二英语竞赛试题 三）单项选择 1. There is nobody in the room, _____________? A.is there B. isn’t there C. is it D. isn’t it 2. -_______you ever________to Beijing? -No, I haven’t. A. Do, been B. Have, been C. Have, being D. Do, be 3. -How about getting her a CD? -No, that’s not____________. A. specially B. enough specially C. specially enough D. enough 4. Do you often help Wei Fang_________her lessons? A. in B. at C. with D. out 5. Mum is busy on Sunday. She is the________in my family. A. busy B. busier C. busiest D. most busy 6. Is____________in bed good or bad for your health? A.read B. reading C. readed D. reads 7. I hope_______tomorrow. A. you’re better B. you’d better C. your better D. you had
一、单选题 1.Java JDK中调试器的命令是( )。 A. javac B. java C. jdb D. javah 2.运行jar文件中class文件需要在java命令后面加的参数为（）。 A. -cp B. -g C. -d D. -verbose 3.下面哪项在java中是不合法的标识符？（） A. $user B. point C. You&me D. _endline 4.下列哪一项不是Java保留字？（） A. sizeof B. super C. abstract D. break 5.下列哪个布局管理器中的按钮位置有可能会根据Frame的大小改变而改变？ （） A. BorderLayout B. CardLayout C. GridLayout D. FlowLayout 6.下面哪些java语句会导致无限循环?( ) I. while (true) i = 0; II. while (false) i = 1; III. while (!false) i = 0; A. III only B. I and III only C. I only D. I, II and III 7.下面是Example.java文件的完整代码，请找出会产生编译错误的行（）。 １) class BaseClass { ２) public String str; ３) public BaseClass(){ ４) System.out.println(“ok”);} ５) public BaseClass(String s){ ６) str=s;}} ７) class SubClass extends BaseClass{ ８) } 9) public class Example{ 10) public void method(){ 11) SubClass s=new SubClass(“hello”); 12) BaseClass b=new BaseClass(“world”); 13) } 14) } A. 7 B. 10 C. 11 D.12 8.可以在下面代码段point x处写入的是（）。 //point x public class Interesting{ //do something } A. String str; B. static int PI=3.14; C. public class MyClass{//do other thing…} D. import java.awt.*; 9.下面关于事件监听的说明，哪一个语句是正确的？（） A. 所有组件，都不允许附加多个监听器 B. 如果多个监听器加在一个组件上，那么事件只会触发一个监听器 C. 组件不允许附加多个监听器
第31届全国中学生物理竞赛复赛理论考试试题解答 2014年9月20日 一、（12分） （1）球形 （2）液滴的半径r 、密度ρ和表面张力系数σ（或液滴的质量m 和表面张力系数σ） （3）解法一 假设液滴振动频率与上述物理量的关系式为αβγρσ=f k r ① 式中，比例系数k 是一个待定常数. 任一物理量a 可写成在某一单位制中的单位[]a 和相应的数值{}a 的乘积{}[]=a a a . 按照这一约定，①式在同一单位制中可写成 {}[]{}{}{}{}[][][]αβγαβγρσρσ=f f k r r 由于取同一单位制，上述等式可分解为相互独立的数值等式和单位等式，因而 [][][][]αβγρσ=f r ② 力学的基本物理量有三个：质量m 、长度l 和时间t ，按照前述约定，在该单位制中有 {}[]=m m m ，{}[]=l l l ，{}[]=t t t 于是 [][]-=f t 1 ③ [][]=r l ④ [][][]ρ-=m l 3 ⑤ [][][]σ-=m t 2 ⑥ 将③④⑤⑥式代入②式得[][]([][])([][])αβγ---=t l m l m t 132 即[][][][]αββγγ--+-=t l m t 132 ⑦ 由于在力学中[]m 、[]l 和[]t 三者之间的相互独立性，有 30αβ-=， ⑧ 0βγ+=， ⑨ 21γ= ⑩ 解为311 ,,222αβγ=-=-= ?将?式代入①式得 σρ=f k r 3 解法二 假设液滴振动频率与上述物理量的关系式为αβγρσ=f k r ① 式中，比例系数k 是一个待定常数. 任一物理量a 可写成在某一单位制中的单位[]a 和相应的数值{}a 的乘积{}[]=a a a . 在同一单位制中，①式两边的物理量的单位的乘积必须相等[][][][]αβγρσ=f r ② 力学的基本物理量有三个：质量M 、长度L 和时间T ，对应的国际单位分别为千克（kg ）、米（m ）、秒（s ）. 在国际单位制中，振动频率 f 的单位[]f 为s -1 ，半径r 的单位[]r 为m ，密度ρ的单位[]ρ为 3kg m -?，表面张力系数σ的单位[]σ为1 2 1 2N m =kg (m s )m kg s ----????=?，即有 []s -=f 1 ③ []m =r ④ []kg m ρ-=?3 ⑤ []kg s σ-=?2 ⑥ 若要使①式成立，必须满足 () ()s m kg m kg s (kg)m s β γ αβγαβγ ---+--=??=??13232 ⑦ 由于在力学中质量M 、长度L 和时间T 的单位三者之间的相互独立性，有 30αβ-=， ⑧ 0βγ+=， ⑨