1、2021湖北武漢中考成績查詢網(wǎng)址篇一：2021年武漢市中考物理試題(清晰版)2021年武漢市初中畢業(yè)生學(xué)業(yè)考試物理試題 一選擇題（36分） 9.下列措施中，不能減弱噪聲的是 A摩托車的消聲器 B居民區(qū)旁高架橋上的隔音擋板 C學(xué)校附近安裝噪聲監(jiān)測裝置 D工廠用的防噪聲耳罩 10.關(guān)于熱現(xiàn)象，下列說法正確的是 A干冰給食品保鮮，利用了干冰熔化吸熱 B把酒精擦在手背上，手背感覺涼爽，是由于酒精汽化放熱 C一瓶水被冰箱冷凍后，取出放一會兒，表面會濕，是由于水蒸氣液化 D北方的冬天，為了保存蔬菜，在菜窖里放幾桶水，利用了水凝華放熱 11.關(guān)于光現(xiàn)象，下列說法錯誤的是 A影的形成，是光的直線傳播 B玻璃幕

2、墻反射的光會“晃”著人們的眼睛，是由于光發(fā)生了漫反射 C小芳面向穿衣鏡站在鏡前1m處，當(dāng)她遠(yuǎn)離平面鏡后退0.5m時，鏡中的像與她相距3m D“海市蜃樓”的形成，是由于發(fā)生了折射 12.關(guān)于信息的傳遞與能源，下列說法正確的是 A手機(jī)是利用電磁波傳遞信號 B“北斗”導(dǎo)航系統(tǒng)是利用超聲波進(jìn)行定位和導(dǎo)航 C目前核電站是利用核聚變發(fā)電 D太陽能的利用具有廣闊的前景，所以人類不再有能源危機(jī) 13.如圖所示，GMR是巨磁電阻，它的阻值隨電磁鐵磁性的增強(qiáng)而減小。下列判斷正確的是 A開關(guān)S1閉合，滑片移到某一位置，電磁鐵左端為N極 B開關(guān)S2閉合，滑片向右移動，電磁鐵磁性增強(qiáng) C開關(guān)S1和S2同時閉合，滑片向右

3、移動，GMR的電阻變小 D開關(guān)S1和S2同時閉合，滑片向左移動，指示燈變暗 14.如圖是手搖發(fā)電機(jī)的構(gòu)造示意圖。搖動手柄，線圈在磁場中轉(zhuǎn)動 ，小燈泡發(fā)光。下列實驗中和手搖發(fā)電機(jī)工作原理相同的是 15.關(guān)于某中學(xué)生的估測，下列數(shù)據(jù)合理的是 A身高約為160dm B。100m的短跑成績約為6s C步行的速度約為1m/s D。脈搏正常跳動60次所用時間約為1s。 16.為了測量某金屬塊的密度，首先用天平測量金屬塊的質(zhì)量，當(dāng)天平平衡時，右盤中的砝碼質(zhì)量和游碼的位置如圖甲所示。然后用量筒和水測量金屬塊的體積如圖乙所示。下列數(shù)據(jù)正確的是 A金屬塊的質(zhì)量為39.4g B金屬塊的體積為5L C金屬塊的密度為7

4、.8103kg/m3 D金屬塊的密度為7.88g/cm3 17.如圖是太陽能汽車在平直公路上勻速行駛的情形，若不計空氣對汽車的影響，則下列說法正確的是 A汽車的重力和地面對汽車的支持力是相互作用力 B汽車受到兩對平衡力的作用 C汽車急剎車時不能立即停止，是由于速度大慣性大 D太陽能汽車行駛時是將太陽能直接轉(zhuǎn)化成機(jī)械能 18.如圖分別是小明家上月初和月末的電能表的表盤，表盤上“1600imp/kw.h”表示每消耗1kw.h的電能，指示燈閃爍1600次，下列選項正確的是 A指示燈閃爍越快。電能表所在電路消耗的電能越多 B小明家上月消耗的電能為911kw.h C小明家干路中的電流不得超過10A D斷

5、開其他用電器，只讓電飯鍋單獨工作2min，指示燈閃爍32次，此時電飯鍋的功率為600W。 19.如圖所示，學(xué)校有前后兩個門和值班室。在前、后門各裝一個按鈕開關(guān)，學(xué)校值班室有 電池組、電鈴和紅、綠兩盞燈。要求：前門來人按下開關(guān)時，紅燈亮且電鈴響；后門來人按 下開關(guān)時，綠燈亮且電鈴響。以下電路設(shè)計符合要求的是 20.如圖所示的電路，燈泡上標(biāo)著“2.5V 0.25A”，電流表和電壓表的量程分別為00.6A和03V 斷開S1和S3，閉合S2，將滑片移到阻值最大處時，滑動 變阻器接入電路的阻值為R2，R2消耗的功率為0.162W，電 壓表和電流表的示數(shù)分別為U1和I1. 斷開S2，閉合S1和S3時，電壓

6、表和電流表的示數(shù)分別為 U2和I2. 斷開S3，閉合S1和S2，移動滑片，使滑動變阻器接入電 路的阻值為3R2/4時，電流表的示數(shù)I3=2I1 已知U1：U2=9：5I1：I2=3：5 ，假設(shè)燈泡的電阻和電源電壓不變，則下列數(shù)據(jù)錯誤的是 AR1=20 B在中，為了保證電路安全，滑動變阻器阻值變化范圍為420 C在中，電路消耗的總功率為0.81W D電源電壓為4.5V 第卷 二非選擇題 21（3分）搬運磚頭的獨輪車，車廂和磚頭所受的總重力G=1400N。 獨輪車有關(guān)尺寸如圖所示。該獨輪車是一個 杠桿，動力 。為了更省力，工人師傅可以采取的措施是 （寫一條即可） 22（3分）甲、乙兩地之間沿直線架

7、設(shè)了兩條輸電線，輸電 線的線芯用銅導(dǎo)線，是為了減少因電流的 效應(yīng)而損失 的電能。已知每條輸電線每千米的電阻為0.2，現(xiàn)輸電線在 某處發(fā)生了短路，為了確定短路的位置，檢修員在甲地將電流 表接入如圖所示的電路，電壓表應(yīng)接在（選填“AB” 或“CD”）兩點之間：若電壓表和電流表的示數(shù)分別為4V和 0.5A，則短路的位置距離甲地。 23（3分）某同學(xué)用如圖甲所示的實驗裝置，比較不同物質(zhì)的比熱容和探究水沸騰時溫度變化的特點。將分別盛有相同質(zhì)量的水和食用油的兩個試管固定在鐵架臺上， 溫度傳感器的探頭與水和食用油良好接觸，將溫度傳感器與計算機(jī)相連，計算機(jī)上顯示的實驗圖線如圖乙所示。 由圖乙可知：水沸騰時吸熱

8、，溫度 （選填“升高”、“不變”或“降低”）；加熱2min 水吸收的熱量、“等于”或“小于”）食用油吸收的熱量；食用油的比熱容為 J/(kg.)。 24（4分）在探究凸透鏡成像規(guī)律的實驗中 （1）如圖所示，已知凸透鏡的焦距f=15cm。保持光屏和凸透鏡的位置不變，要使?fàn)T焰在光 屏上成清晰的像，蠟燭應(yīng) （選填“靠近”或“遠(yuǎn)離”）凸透鏡，將近視鏡片放在蠟燭和凸透鏡之間，光屏上原來清晰的像變模糊了；使光屏遠(yuǎn)離凸透鏡，又能在光屏上看到清晰的像。這說明近視眼鏡對光線具有作用。由此可知，在近視眼得到矯正之前，蠟燭的像成在視網(wǎng)膜的 （選填“前方”、“上方”或“后方”） 25（6分）利用如圖甲所示的電路探究電

9、流跟電壓的關(guān)系，電源電壓6V不變。 （1）按圖甲，在圖乙中把接錯的一根導(dǎo)線打上“”，再畫線把它改到正確的位置上。 （2）正確連接電路后，再閉合開關(guān)，移動滑片，發(fā)現(xiàn)電壓表和電流表示數(shù)均為0；繼續(xù)移動滑片，當(dāng)兩電表指針剛好偏轉(zhuǎn)且穩(wěn)定時，其示數(shù)見序號3.繼續(xù)實驗，數(shù)據(jù)見序號4和序號5. 根據(jù)第5組數(shù)據(jù)，在圖丙中用“”標(biāo)出電流表指針?biāo)诘奈恢谩?由序號1、2兩組數(shù)據(jù)可判斷，該電路故障為（選填“R1接觸不良”、“R2斷路”或“R2短路”） 序號3、4、5三組數(shù)據(jù)表明：在導(dǎo)體的 一定時，導(dǎo)體中的電流跟導(dǎo)體兩端的電壓成正比。 根據(jù)表中的數(shù)據(jù)計算，滑動變阻器接入電路的最大阻值為 ，滑動變阻器的功率變化了W。

10、26（5分）為了探究浮力大小跟哪些因素有關(guān)，某興趣小組的同學(xué)，用同一物體進(jìn)行了如圖所示的操作，并記下物體靜止時彈簧測力計的示數(shù)。圖乙中物體未放入前溢水杯裝滿水，物體浸沒后用量筒測出溢出水的體積，如圖丁所示。 （1）為了探究浮力的大小與液體密度的關(guān)系，應(yīng)選擇兩圖；該小組同學(xué)通過比較F1和 的大小，得到“浮力的大小與物體浸沒的深度有關(guān)”的結(jié)論，產(chǎn)生錯誤的原因是。 （2）物體浸沒在水中時所受浮力大小為 N，鹽水的密度為 kg/m3篇二：完整版2021湖北省武漢英語中考真題及答案 英語試卷 第一卷（選擇題 共85分） 第一部分 聽力部分 聽力測試（共三節(jié)） 第一節(jié)（共5小題，每小題1分，滿分5分） 聽

11、下面5個問題，每個問題后有三個答語，從題中所給的A、B、C三個選項中選出最佳選項。聽完每個問題，你都有5秒鐘的時間來作答和閱讀下一小題，每個問題僅讀一遍。 ()1. A. A nice plate.B. Delicious. C. For Kate. ()2. A. A black cat. B. Very heavy. C. Its black. ()3. A. In the meeting room. B. At eight thirty.C. For about one hour. ()4. A. Its a nice one. B. The smaller one. C. High i

12、n the sky. ()5. A. This afternoon. B. With Jenny. C. In the office. 第二節(jié)（共7小題，每小題1分，滿分7分） 聽下面7段對話。每段對話后有一個小題，從題中所給的A、B、C三個選項中選出最佳選項。聽完每個問題，你都有時間來作答和閱讀下一小題。每個問題僅讀一遍。 ()6. Who sings well? A. Mary. B. Kate.C. The classmates. ()7. How will the man probably go to the hotel? A. On foot.B. By bus. C. By sub

13、way. ()8. What happened to the boy? A. He was late for school. B. He went to see a doctor. C. His father left him alone home. ()9. Who thinks history is not as popular as art? A. The man.B. The woman. C. Both of them. ()10. Whats the time now? A. 10:15 B. 10:30 C. 10:45 ()11. Where are the two peopl

14、e? A. In the mans office. B. In the womans home. C. In a restaurant. ()12. What does the woman mean? A. She has just bought a new car. B. She has no time to help the man. C. She will drive the man to the station. 第三節(jié)（共13小題，每小題1分，滿分13分） 聽下面4段對話或獨白，每段對話或獨白后有幾個小題，從題中所給的A、B、C三個選項 中選出最佳選項，聽每段對話或獨白前，你將有時間

15、閱讀各個小題，每小題5秒鐘，聽完后，各小題將給出5秒鐘的作答時間，每段對話或獨白讀兩遍。 聽下面一段對話，回答13至15三個小題。 ()13. Whats David doing? A. Shopping online. B. Playing computer games. C. Studying English. ()14. How much will the woman pay for the dictionary?A. 60yuan B. 35yuan C. 25yuan ()15. Whats the possible relationship between the two spea

16、kers? A. Buyer and seller. B. Mother and son. C. Teacher and students. 聽下面一段對話，回答16至18三個小題。 ()16. When does this conversation take place? A. In the morning. B. In the afternoon. C. In the evening. ()17. Why wont the woman go to karaoke? A. She doesnt like it. B. She cant sing very well. C. She doesn

17、t want to go out. ()18. What are they going to do at last? A. Have dinner. B. Sing songs. C. Watch TV. 聽下面一段對話，回答19至22三個小題. ()19. Who do you think the man is? A. A stranger.B. A friend. C. A family member ()20. What do we know about the woman? A. She likes her hometown. B. She knows little about Wuh

18、an. C. Shes never been away from Wuhan. ()21. Which of the following used to be the oldest? A. The science museum. B. The city library.C. The park. ()22. What does the woman suggest doing? A. Climbing the hills. B. Having a meal. C. Seeing more places. 聽下面一段對話，回答23至25三個小題 ()23. What happened while M

19、r Smith was reading? A. A ball hit him on the head. B. Some boys went to visit him. C. Someone gave the ball back to him. ()24. Where was the ball finally found? A. In the office.B. On the playground.C. Beside the window. ()25. What do you think Mr Smith most probably was? A. A football player.B. A

20、policeman.C. A teacher. 第二部分 筆試部分 二、選擇填空（本題共15分，每小題1分） ()26. -Would you like to play basketball with us this afternoon? - A. I dont care B. Its very nice of you C. Of course not D. My pleasure ()27. -Who is that Lady?-She us music, and she is so good. A. taughtB. teaches C. will teach D. is teaching

21、 ()28. -So sorry, Tom. I cant find the book you me. -Its OK, I dont need it anymore. A. lend B. have lent C. will lend D. lent ()29. -I dont feel well, Jack. Im afraid you me your cold? A. gave B. had givenC. have given D. would give ()30. -Whats the matter, Jenny? - something wrong with my bike. A.

22、 It isB. There is C. I have D. It has ()31. -I had a pleasant winter vacation with my family in the north? - . A. Oh, thats very nice of you. B. Enjoy yourself C. Well done!D. Glad to hear that ()32. -I think students can have mobile phones to help with their studies. - . They often use them to play

23、 games. A. I think so B. I dont agree C. No problem D. Thats a good idea ()33. -There re four bedrooms in the house,with its own shower. -Thats what I want. Ive got a few kids. A. either B. neither C. eachD. none ()34. -Come home before dinner time, Peter! - I , Mom. A. promise B. guessC. wish D. ad

24、mire ()35. -Are you alone? I just want a word with you. A. single B. new C. private D.certain ()36. -Look, the boss is angry with Alex. -Well, be came late again. But thats no to shout at him. A. problem B. lessonC. excuse D. reason ()37. -Her father tried to that nothing unusual had happened . -In

25、fact, it was not serious. A. imagine B. pretend C.mean D. warn ()38. -Why did she your invitation? -Because she had an important meeting to attend that day. A. turn downB. put away C. look up D. hand in ()39. -I still havent found my pet dog. -Im sorry to hear that. You be very sad. A. canB. should

26、C. must D. will ( )40. -What did the teacher say to you? -He asked me . A. why I look unhappy then B. when did I go home last night C. how could I solve the problem D. if i had got everything ready 三、完型填空（共15小題，每小題1分，滿分15分） 閱讀下面短文，從短文后各題所給的四個選項（A、B、C、D）中，選出可以填入空白處的最佳答案。 A jobless man wanted to apply

27、(求職)for the position of “office boy” at Microsoft. The staff manager interviewed him and then gave him a : clean the floor. The man passed it; he cleaned the floor very well. “you are hired（解雇），” the manager told the man “Give me your email address, and Ill send you the form to you should report for

28、 the work.” The man replied, “I dont have a or email! ” “Im sorry,” said the manager. “If you dont have email, that means you do not exist（存在）”.And we cannot 45 persons who do not exist.” The man was very . He didnt know what to do. He only had 10 dollars with him. Once that was . He wouldnt have an

29、y money to buy even food. He went to the supermarket and bought a box of tomatoes with his 10 dollars. He went from door to door and the tomatoes in small bags. He doubled his money. He this three times, and returned home with 60 dollars. He realized that he could continue to live this way. He start

30、ed to go earlier every day, and return later. He doubled or made even three times his money every day. Soon, he a cart, then a truck. In a very short time, he had his many delivery(遞送)trucks. Five years later, the man became one of the biggest sellers in the country. He started to plan his familys f

31、uture. He called an insurance(保險)broker, a man sells insurance. At the end of the “I dont have an email. ” Hearing that, the broker felt very “You dont have email, and yet have succeeded in becoming so Can you imagine what you could have been if you had email?” He said aloud. The man thought for a w

32、hile, and replied, “an office at Microsoft!” If you just lost your job or just failed an interview, dont worry, think of the positive(積極的).Good days are on the way and something better will happen to you. ()41. A. jobB. handC. chanceD. test ()42. A. check out B.put up C. fill in D. write down ()43.

33、A. name B. date C. address D. ticket ()44. A. computer B. screen C. website D. letter ()45. A.believe B. pay C. acceptD. refuse ()46. A. pleasedB. excited C. embarrassed D. disappointed ()47. A.exchanged B. spentC. wastedD. lost ()48. A. dividedB. showed C. kept D. sold ()49. A. repeated B. reminded

34、C. tried D. counted ()50. A. borrowed B. repaired C. received D. bought ()51. A. truck B. insurance C. food D. door ()52 A. introductionB. conversation C. business D. story ()53. A. worriedB. satisfied C. upsetD. surprised ()54. A. clever B. healthy C. rich D. confident ()55. A. boy B. secretary C.

35、cleaner D. head B Andrew Holleman, a 12-year-old boy, loved playing in the open land near his home. The land waswet and forested, and made a home for the birds, other animals and many different plants. It made the perfect place for him to study and get to know the nature. He had seen some red-tailed

36、 hawks, red foxes, wood turtles and other animals. He also found special native flowers. Suddenly it was announced that the “empty” land would be improved by a lot of houses on it. The plants would be removed, the animals would run away and most would probably die. Then the wet soil would be covered

37、 with extra grounds. When he heard about the news, he was not happy. He was very worried that the land and water would be polluted. Andrew wrote down clearly all the research be had down about the area, and how the houses would affect the local environment. He sent letters to members of local govern

38、ment and Although he was only 12 years old, he had the courage and wisdom of a person much older. Andrews teachers described him as gentle, shy and active. His classmates also admired how much he knew about local animals and plants, and the environment. Each day after school, Andrew went door-to-doo

39、r, to ask the people to sign, who did not want the houses to be built. It only one month, he got the signatures of 250 people. In the end, the land remained a safe place for birds, animals and plants that belonged there. Andrew won many prizes for his brave and great work to stop the houses being bu

40、ilt, and thus help save the environment. ()61. The passage is mainly about . A. 250 people who signed to help Andrew B. A brave boy who cared for the environment C. The open land that suited animals and plants D. The research of improving the environment ()62. The underline word “oppose” in the pass

41、age probably means . A. support. B. dislike C. disagree D. prefer ()63.Andrew was very worried because A. The animals would be killedB. New houses would be built on the open land C. Not all the neighbors were going to sign D. The local government made a right decision ( . A. Was good at going door-t

42、o-door B. Got in no touch with the reporters C. Usually acted like a person much older D. Was praised by his teachers and classmates ()65. We can inter that . A. The land would remain as it used to be B. The open land would be built into a park C. The neighbors would have to move away D. Andrew woul

43、d soon work for the government c The National Football League is a professional American football league with 32 teams in. How does one choose which team to support? Some people choose the team of their hometown, or where they now live, or the team that their parents or their friends follow.篇三：2021年

44、武漢中考物理含答案 2021年武漢市初中畢業(yè)生學(xué)業(yè)考試物理試題 一選擇題（36分） 9.下列措施中，不能 減弱噪聲的是 A摩托車的消聲器 B居民區(qū)旁高架橋上的隔音擋板 C學(xué)校附近安裝噪聲監(jiān)測裝置 D工廠用的防噪聲耳罩 10.關(guān)于熱現(xiàn)象，下列說法正確的是 A干冰給食品保鮮，利用了干冰熔化吸熱 B把酒精擦在手背上，手背感覺涼爽，是由于酒精汽化放熱 C一瓶水被冰箱冷凍后，取出放一會兒，表面會濕，是由于水蒸氣液化 D北方的冬天，為了保存蔬菜，在菜窖里放幾桶水，利用了水凝華放熱 11.關(guān)于光現(xiàn)象，下列說法錯誤 的是 A影的形成，是光的直線傳播 B玻璃幕墻反射的光會“晃”著人們的眼睛，是由于光發(fā)生了漫反射

45、 C小芳面向穿衣鏡站在鏡前1m處，當(dāng)她遠(yuǎn)離平面鏡后退0.5m時，則鏡中的像與她相距3m D“海市蜃樓”的形成，是由于發(fā)生了折射 12.關(guān)于信息的傳遞與能源，下列說法正確的是 A手機(jī)是利用電磁波傳遞信號 B“北斗”導(dǎo)航系統(tǒng)是利用超聲波進(jìn)行定位和導(dǎo)航 C目前核電站是利用核聚變發(fā)電 D太陽能的利用具有廣闊的前景，所以人類不再有能源危機(jī) 13.如圖所示，GMR是巨磁電阻，它的阻值隨電磁鐵磁性的增強(qiáng)而減小。下列判斷正確的是 A開關(guān)S1閉合，滑片移到某一位置，電磁鐵左端為N極 B開關(guān)S2閉合，滑片向右移動，電磁鐵磁性增強(qiáng) C開關(guān)S1和S2同時閉合，滑片向右移動，GMR的電阻變小 D開關(guān)S1和S2同時閉合，

46、滑片向左移動，指示燈變暗 14.如圖是手搖發(fā)電機(jī)的構(gòu)造示意圖。搖動手柄，線圈在磁場中轉(zhuǎn)動，小燈泡發(fā)光。下列實驗中和手搖發(fā)電機(jī)工作原理相同的是 15.關(guān)于某中學(xué)生的估測，下列數(shù)據(jù)合理的是 A身高約為160dm B。100m的短跑成績約為6s C步行的速度約為1m/s D。脈搏正常跳動60次所用時間約為1s。 16.為了測量某金屬塊的密度，首先用天平測量金屬塊的質(zhì)量，當(dāng)天平平衡時，右盤中的砝碼質(zhì)量和游碼的位置如圖甲所示。然后用量筒和水測量金屬塊的體積如圖乙所示。下列數(shù)據(jù)正確的是 A金屬塊的質(zhì)量為39.4g B金屬塊的體積為5L C金屬塊的密度為7.8103kg/m3 D金屬塊的密度為7.88g/c

47、m3 17.如圖是太陽能汽車在平直公路上勻速行駛的情形，若不計空氣對汽車的影響，則下列說法正確的是 A汽車的重力和地面對汽車的支持力是相互作用力 B汽車受到兩對平衡力的作用 C汽車急剎車時不能立即停止，是由于速度大慣性大 D太陽能汽車行駛時是將太陽能直接轉(zhuǎn)化成機(jī)械能 18.如圖分別是小明家上月初和月末的電能表的表盤，表盤上“1600imp/kw.h”表示每消耗1kw.h的電能，指示燈閃爍1600次，下列選項正確的是 A指示燈閃爍越快。電能表所在電路消耗的電能越多 B小明家上月消耗的電能為911kw.h C小明家干路中的電流不得超過10A D斷開其他用電器，只讓電飯鍋單獨工作2min，指示燈閃爍

48、32次，此時電飯鍋的功率為600W。 19.如圖所示，學(xué)校有前后兩個門和值班室。在前、后門各裝一個按鈕開關(guān)，學(xué)校值班室有電池組、電鈴和紅、綠兩盞燈。要求：前門來人按下開關(guān)時，紅燈亮且電鈴響；后門來人按下開關(guān)時，綠燈亮且電鈴響。以下電路設(shè)計符合要求的是20.如圖所示的電路，燈泡上標(biāo)著“2.5V 0.25A”，電流表和電壓表的量程分別為00.6A和03V 斷開S1和S3，閉合S2，將滑片移到阻值最大處時，滑動變阻器接入電路的阻值為R2，R2消耗的功率為0.162W，電壓表和電流表的示數(shù)分別為U1和I1. 斷開S2，閉合S1和S3時，電壓表和電流表的示數(shù)分別為U2和I2. 斷開S3，閉合S1和S2，

49、移動滑片，使滑動變阻器接入電路的阻值為3R2/4時，電流表的示數(shù)I3=2I1 已知U1：U2=9:5I1：I2=3:5 ，假設(shè)燈泡的電阻和電源電壓不變，則下列數(shù)據(jù)錯誤的是 AR1=20 B在中，為了保證電路安全，滑動變阻器阻值變化范圍為420 C在中，電路消耗的總功率為0.81W D電源電壓為4.5V 二非選擇題 21.（3分）搬運磚頭的獨輪車，車廂和磚頭所受的總重力G=1400N。獨輪車有關(guān)尺寸如圖所示。該獨輪車是一個 杠桿，動力F= 。為了更省力，工人師傅可以采取的措施是（寫一條即可） 第21題圖 第22題圖 第23題圖 22. （3分）甲、乙兩地之間沿直線架設(shè)了兩條輸電線，輸電線的線芯用銅導(dǎo)線，是為了減少因電流的效 應(yīng)而損失的電能。已知每條輸電線每千米的電阻為0.2，現(xiàn)輸電線在某處發(fā)生了短路，為了確定短路的位置，檢 修員在甲地將電流表接入如圖所示的電路，電壓表應(yīng)接在（選填“AB”或“CD”）兩點之間：若電壓表 和電流表的示數(shù)分別為4V和0.5A，則短路的位置距離甲地 km。 23. （3分）某同學(xué)用如圖甲所示的實驗裝置，比較不同物質(zhì)的比熱容和