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新人教版高中英語必修2Unit 1 Cultural Heritage-Discovering Useful Structure教案二
This theme of the part is “ Describe people or things in greater detail”. Students have learned the grammar(restrictive relative clauses) in Book 1, and further review and consolidate its structure “prep+relative pronouns(which/whom)” and the relative adverbs(when, where and why), besides students should understand its form, meaning and functions. In this section, students should be able to express the grammar correctly in daily communication and in the writing. 1. Review the basic usages of relative pronouns and adverbs of attributive clauses . 2. Learn to use some special cases about restrictive relative clauses.3. Learn to write sentences with restrictive relative clauses flexibly according to the context.1. Review the basic usages of relative pronouns and adverbs of attributive clauses .2. Learn to use some special cases about restrictive relative clauses.3. Learn tow rite sentences with restrictive relative clauses flexibly according to the context.Step 1. Observe the following sentences, and mark the relative pronouns and the adverbs. 1. After listening to the scientists who had studied the problems, and citizens who lived near the dam, the government turned to the United Nations for help.2. Temples and other cultural sites were taken down piece by piece, and then moved and put back together again in a place where they were safe from the water.Step 2 PracticePlease complete these sentences with relative pronouns and relative adverbs and answer the following questions.Questions: 1. What is the head noun ?2. What relative words should be used ?3. What elements do they act in these sentences ?
新人教版高中英語必修2Unit 3 The Internet-Discovering Useful Structure教案二
This teaching period mainly deals with grammar “The Present Perfect Passive Voice.” To begin with, teachers should lead students to revise what they have learned about the Present Perfect Passive Voice. And then, teachers move on to stress more special cases concerning this grammar。This period carries considerable significance to the cultivation of students’ writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercises. 1. Guide students to review the basic usages of the Present Perfect Passive Voice2. Lead students to learn to use some special cases concerning the Present Perfect Passive Voice flexibly.2. Enable students to use the basic phrases structures flexibly.3. Strengthen students’ great interest in grammar learning.1. Help students to appreciate the function of the Present Perfect Passive Voice in a sentence2. Instruct students to write essays using the proper the Present Perfect Passive Voice.觀察下列句子特點，總結共同點。1．(教材P28)Much has been written about the wonders of the World Wide Web．2．(教材P28)But the Internet has done much more for people than simply make life more convenient．3．(教材P28)Many people have been helped by the club．4．(教材P28)She no longer feels lonely, and her company has become quite successful．5．(教材P32)Today I thought I’d blog about a question that has been asked many times—how do you stay safe online and avoid bad experiences on the Internet?
新人教版高中英語必修2Unit 4 History and Traditions-Discovering Useful Structure教案一
Step 5 Practice一、完成下列句子。1. Judy and I _______________（把車停下來(park)）in an underground car Park near Trafalgar Square, where we could ______________________(讓我們的車充電（charge)).2. When we finally reached the service desk to ask for audio guides, we heard it ___________ that there were no audio guides____________(留下，剩下）.3. We__________________________（發(fā)現(xiàn)自己對...很驚訝）the large number of visitors and the amount of noise at the entrance of the National Gallery.4. Judy ____________________(眼神專注于） Van Gogh’s Sunflowers. It was hard to approach the painting as there were so many people around.5. She ____________________(把這幅畫的復制品裝箱（box)） to ensure that it was delivered safely.答案：1.had our car parked get our car battery charged 2. announced left 3. found ourselves very surprised 4. had her eyes fixed on 5. had a copy of the painting boxed二、用過去分詞對下列句子進行改寫。1. Loch Ness was surrounded by beautiful natural landscape, which made it look amazing.2. Carl and his friend stayed with a generous family who offered them bread with butter and honey that was homemade.3. The family’s ancestors once attended to soldiers who were wounded in the First World War.4. The young people were attracted by the legend of Loch Ness. They watched over the lake with their cameras and binoculars, which were positioned on the hill.答案：1. Loch Ness surrounded by beautiful natural landscape looks amazing.2. Carl and his friends stayed with a generous family who offered them homemade bread with butter and honey.3. The family’s ancestors once attended to wounded soldiers in the First World War.4. The young people attracted by the legend of Loch Ness watched over the lake with their cameras and binoculars positioned on the hill.
新人教版高中英語必修2Unit 3 The Internet-Reading and Thinking教案一
Paragraph 3. Jan decided to start an IT club to teach old people how to use computers and the Internet. Paragraph 4. Jan has started taking online classes to learn more about how to use the Internet to make society better. Paragraph 5. Jan’s life has been greatly improved by the Internet. Step 5: Critical thinking:(1)How do you arrange your time spent on study and the Internet? Is it reasonable? I usually surf the Internet using my mobile phone for only an hour after class, and it is reasonable for me.(2)What are your online activities? Are they safe? I chat with my friends, read news and play games. I never give away my private information so I think they are safe.Step 4: summary Much has been written about the wonders of the World Wide Web. There are countless articles (1)______(tell) us how the Internet has made our lives more convenient. But the Internet has done a lot (2)_____(much) for people than simply make life more convenient. People’s lives (3) _________________(change) by online communities and social networks so far. Take Jan for example, who developed a serious illness that made her (4)_____(stick) at home with only her computer to keep (5)___(she) company. She joined an online group (6)______ she could share problems, support and advice with others. She considered the ability to remove the distance between people as one of the greatest (7)_______(benefit). She was so inspired (8)____ she started an IT club in which many people have been helped. She has started to learn more about how to use the Internet to make society better. Her next goal is to start a charity website to raise money (9)___ children in poor countries. Jan’s life has been (10)______(great) improved by the Internet. Step 5 Homework:Review what we have learned and find out the key language points in the text.
新人教版高中英語必修2Unit 4 History and Traditions-Listening＆Speaking＆Talking教案一
This unit is about history and traditions. From the opening page, we can know that this unit will introduce the history and traditions around the world. As Marcus Garvey says “A people without the knowledge of their past history, origin and culture is like a tree without roots”, it is important for students to realize the importance and value of knowing the history and traditions and their further meanings. And this part ( listening and speaking ) is divided into two parts: Part A---share views on historic sites, Part B ---talk about a visit to a historic tourist destination. By talking with a foreigner, the speakers introduce the historic attractions and their cultures. Part A is that William, a British student, who was going to visit the Confucius Temple and a Chinese student, Xiao Kong, who was going to the Confucius Temple to meet with the members of the research group, went together and exchanged their views on the Confucius Temple, Confucius, Confucius' descendants and Confucius' educational thoughts. Part B is a conversation between Xiao Yan, a youth hostel receptionist and Paul, a backpacker about the feelings and experience after visiting the Chinese famous tourist attraction Pingyao.1. Guide students to understand the content of listening texts in terms of the whole and key details; 2. Cultivate students' ability to guess the meaning of words in listening; discuss with their peers how to talk about historic spots and great person.3. Instruct students to use functional sentences of showing one’s excitement, surprise and disappointment.1. Guide students to understand the content of listening texts in terms of the whole and key details; 2. Cultivate students' ability to discuss with their peers the related topics.3. Enable students to use the functional items of showing one’s excitement, surprise and disappointment.
新人教版高中英語必修2Unit 3 The Internet-Reading for Writing教案二
8. However, the more polite you are, the less likely it is you will be attacked. 然而, 你越有禮貌, 你被攻擊的可能性就越小。 Step 8 Writing---the articleHow to stay safe in the online chat roomToday I thought I’d blog about a question that has been asked many times--- how do you stay safe online and avoid bad experiences in the online chat room ? I’m not an expert, but many years as a blogger have taught me a thing or two.First of all, there’s the golden rule of the Internet: keep out of what makes you uneasy. Don’t post comments or click on anything. Second, protect your privacy. Don’t give out too much private information like your address, phone numbers, the ID numbers, etc. Third, be polite. If you are polite to others on the Internet, you won’t be attacked in normal situation. Finally, don’t believe in others easily and never meet someone you met online alone. It is very dangerous.Have you had any bad experiences online, or do you have some good advice for staying safe? Post your comments below!Step 9 Pair workExchange drafts with a partner. Use this checklist to help your partner revise his/her draft.1. Does the writer tell the reader what he/she know about the topic ?2. Are the tips and suggestions well organised ?3. Has the writer defined the new words ?4. Does the author include examples, comparison, or explanations ?5. Does the writer end by asking readers to leave comments and/or suggestions ?6. Can you find any grammar or spelling mistakes.Step 6 HomeworkPut up your revised draft in the classroom or read it to your class.
新人教版高中英語必修2Unit 5 Music-Discovering Useful Structures教案二
4. When he got absorbed in his world of music, he felt as if he could “see” the beauty of the world around him, like he had in his previous life.P·P as adverbial: _________________________________________________________________.Function: _______________________________________________________________________.Step 5 Solid Complete the passage with the words in brackets in their correct forms.Well known as a successful band, the Impact members show quite a few striking qualities. They never ever give up. When _____________(question) by the media, they are not _____________(discourage) and practise even harder. They are improving themselves by attending several master training class. They are united. _____________(fill with) team spirit, they act as a whole, always aiming for glory. Step 6 Difference and similarity from -ingObserve the following examples.1. He went out, shutting the door behind him.=He went out, ________________________________________________________.2. Not knowing what to do, he went to his parents for help.=__________________________________________, he went to his parents for help.Similarity: _______________________________________________________________________________________________________________________________________________________.Difference : _______________________________________________________________________________________________________________________________________________________.Step Practice1. ________ in a hurry, this article was not so good. 因為寫得匆忙, 這篇文章不是很好。2. ________ carefully, he found something he hadn’t known before. 他仔細讀書時, 發(fā)現(xiàn)了一些從前不知道的東西。3. ________ why he did it, the monitor said it was his duty. 當被問及他為什么要這么做時, 班長說這是他的職責
新人教版高中英語必修2Unit 5 Music-Listening＆Speaking＆Talking教案
choir memberspeople to run food stands people to sell festival ticketspeople to sell music CDspeople to set up equipmentmusical performersStep 2: Listen to the announcement again and answer the questions. ? 1. What kind of songs will Grace Davis sing at the festival?? 2. Who can try out as a performer?? 3. What can those who think they do not have musical talent do?? 4. How can students volunteer to take part?? Talking about preferences:? Would you prefer doing ..?? What would you prefer to do?? Would you rather do .... or ….?? What would you rather do?? I'd prefer .... to ..? I'd rather have ... than .. Step 3: Speaking ProjectWork in groups. Role-play the conversation or make a new one.? Debbie: Where have you been? You missed the announcement about the music festival.? John: I was at the doctor's office. Music festival?? Frank: Yes, it's going to be next month on the school sports field. John, you can play the piano. How about playing it at the festival?? John: Well, I'd rather play the violin. I can play Liang Zhu.? Frank: Wow! Sounds good. What about you, Debbie? ? Debbie: Actually, I don't have much musical ability. I'd prefer just to help out with the crowds.? Frank: You can sell tickets or work at a food stand.? John: So can I assume that the aim of the festival is to raise money?? Debbie: Yes. All of the money will go to charity.
新人教版高中英語必修2Unit 5 Music-Discovering Useful Structures教案一
Step1:自主探究。1．(教材P52)Born(bear) in the USA on 2 January 1970, Whitacre began studying music at the University of Nevada in 1988．2．(教材P52) Moved(move) by this music, he said, “It was like seeing color for the first time．”3．(教材P56)I was very afraid and I felt so alone and discouraged(discourage)．4．(教材P58)Encouraged(encourage) by this first performance and the positive reaction of the audience, I have continued to play the piano and enjoy it more every day．Step2:語法要點精析。用法1：過去分詞作表語1）．過去分詞可放在連系動詞be, get, feel, remain, seem, look, become等之后作表語，表示主語所處的狀態(tài)Tom was astonished to see a snake moving across the floor．湯姆很驚訝地看到一條蛇正爬過地板。Finally the baby felt tired of playing with those toys．終于嬰兒厭倦了玩那些玩具。注意：1）.過去分詞作表語時與被動語態(tài)的區(qū)別過去分詞作表語時，強調(diào)主語所處的狀態(tài)；而動詞的被動語態(tài)表示主語是動作的承受者，強調(diào)動作。The library is now closed．(狀態(tài))圖書館現(xiàn)在關閉了。The cup was broken by my little sister yesterday．(動作)昨天我妹妹把杯子打碎了。2）感覺類及物動詞的現(xiàn)在分詞與過去分詞作表語的區(qū)別過去分詞作表語多表示人自身的感受或事物自身的狀態(tài)，常譯作“感到……的”；現(xiàn)在分詞多表示事物具有的特性，常譯作“令人……的”。
新人教版高中英語必修2Unit 5 Music-Listening and Speaking教案
This lesson is about music. Students can classify the types of music through the instruments and its sound and can talk about their preferences about music, even join some activities and play a role in them according to their musical talents. On the basis, they are guided to use the languages to express their preferences and some plosive sounds and their rules.1. Classify the music types through the instruments and its sound.2. Listen and understand what the speakers’ preferences are and the reasons; talk about their own preferences and give their own reasons, using these sentences: “What kind of music do you like? And why? “ “Because it makes/gives me energy/peaceful.../touches my heart...”.3. Learn some plosives and the rules.4. Join some activities and play a role in them according to the talents. 1. Listen and understand what the speakers’ preferences are and the reasons;2. talk about their own preferences and give their own reasons, using these sentences: “What kind of music do you like? And why? “ “Because it makes/gives me energy/peaceful.../touches my heart...”.3. Learn some plosives and incomplete plosives and its rules.Step 1 Lead inPoint at the pictures on P50 and ask Q1: What are the people doing in the pictures below?Q2: What kind of music they are?Then play the MP3s one by oneStep 2 ListeningTask 1: A reporter from the school newspaper is interviewing students about music. Listen to the interviews. Draw lines between the words to make complete sentences. Some words will not be used.
新人教版高中英語必修2Unit 5 Music-Reading for Writing教案二
The Internet celebrity Gao Yifeng. Years ago, he owned 5 companies and the staffs over 1,000, but during the economy crisis, he became nothing but debt. He was so worried that his hair became white overnight. There was a time when he wanted to killed himself. But after listening to the song Start Over by Liu Huan, he decided to cheer himself up. He started a steamed bun shop and gradually became a national chain shops. Now he became successful again.Walter Haddon said, “Music is the medicine of a troubled mind.” Music contains such a pleasant and inspiring force. Music gave him courage and bravery. When he listened to the song, it made his spirit fly like a kite in the wind. Music gave him strength and brought him relief. It was the rock I leant on to become strong and to get through those hard times. I hope none of us have to go through the same kind of suffering that he did. At the same time, we all go through various periods when we feel sad or alone. During those times, music can help us in the same way that it helped him. I hope we all will somehow begin to treasure music and make it a part of our life. Thank you for your listening !5.Revise your writing each other.Does he/she explain how music has changed his/her/someone else’s life?Are some of the rhetorical devices included and used properly ?Does he/she talk about how music makes him/her/someone feel?Is the first word in each sentences capitalised?Does he/she use correct punctuation ?
人教版高中歷史必修2空前嚴重的資本主義世界經(jīng)濟危機教案
在美國歷史上，很少有像胡佛那樣受到老百姓諷刺、憎惡的總統(tǒng)。用破鐵罐、紙板和粗麻布搭起來的棚戶叫做“胡佛村”，手里提著的裝破爛的口袋叫做“胡佛袋”，鄉(xiāng)下的貧民把破汽車前部鋸掉，套上骨瘦如柴的騾子，叫做“胡佛車” ，在公園長凳上躺著過夜的人用舊報紙裹身取暖，叫做“胡佛毯”，衣袋翻過來，一個錢也找不到，叫做“胡佛旗”，野兔被饑餓的農(nóng)民抓來吃，叫做“胡佛豬”。雜耍演員插科打諢說：“什么?生意好起來了嗎，你的意思是說胡佛死了吧?！薄锝虒W反思：本課內(nèi)容比較條理清楚，旨在說明羅斯福新政實施的背景。備課時考慮將課文順序進行一下調(diào)整，使學生能從較直觀的危機的現(xiàn)象進入本課，較易激發(fā)學生的興趣，再來分析原因?qū)W生也就比較容易接受。在分析原因時通過材料和課文的閱讀，使學生自己通過思考逐步得出結論。而關于胡佛政府的措施的講述，及問題的提出則可讓學生先進行預習，為下一課進入羅斯福新政的學習做好準備。多媒體課件的應用也能使教學活動順利流暢的進行。
人教版高中歷史必修2近代中國經(jīng)濟結構的變動教案
★本課小結：通過學習，我們可以看出鴉片戰(zhàn)爭后，隨著外國資本主義經(jīng)濟的入侵，中國近代經(jīng)濟結構發(fā)生了重大變動：自然經(jīng)濟逐漸瓦解，商品經(jīng)濟日益發(fā)展，中國民族資本主義產(chǎn)生，中國社會經(jīng)濟結構正經(jīng)歷著一場史無前例的大轉(zhuǎn)型。清政府內(nèi)部的洋務派為了維護封建統(tǒng)治，掀起了洋務運動。這次運動在促使本國封建經(jīng)濟瓦解的同時，對民族資本主義的產(chǎn)生起了誘導作用。受外商企業(yè)和洋務運動的誘導，十九世紀六七十年代民族資本主義在中國產(chǎn)生，由于受外國資本與本國封建勢力的壓制，舉步維艱；下節(jié)課，我們將關注中國資本主義的曲折發(fā)展。★問題解答⊙【學思之窗】你認為鄭觀應的批評是否有道理？為什么？參考答案：（1）有道理。（2）原因：①鄭觀應認識到了社會制度層面的“體”與科學技術層面的“用”之間不是等同的關系。
人教版高中歷史必修2物質(zhì)生活與習俗的變遷教案
★教學總結：（1）我國衣著服飾變化的三大階段第一階段（鴉片戰(zhàn)爭后到新中國的建立）：這一階段的階段特征為中式與西式、傳統(tǒng)和現(xiàn)代服飾并存男裝：長袍馬褂、西裝、中山裝 女裝：旗袍（新式與舊式）第二階段（新中國建立后到十一屆三中全會）：這一時期由于政治上的影響，階段特征為衣著樸素，與革命相關的服飾成為主流男裝：列寧裝、中山裝、綠軍裝女裝：列寧裝、布拉基、綠軍裝第三階段（十一屆三中全會后）：階段特征為與世界接軌，異彩紛呈；具體表現(xiàn)在，服飾由最基本的防寒保暖向美觀大方轉(zhuǎn)變，各種款式的服裝層出不窮現(xiàn)在的服裝是色彩鮮艷、款式多樣，什么牛仔服、休閑服、西裝、T恤衫、晚禮服，真是不勝枚舉。每年服裝的流行色、流行款式不斷改變，大街上的姑娘和小伙子永遠領導著時裝新潮流。模特表演、模特廣告和模特大賽已成為人們穿著方面不可缺少的內(nèi)容。
人教版高中語文必修2《成語：中華文化的微縮景觀》教案2篇
七、教學反思這堂課有眼下看得見的效果和暫時看不見的長遠的效果，學生收益明顯：1．學生學到的不只是成語本身。學生從網(wǎng)絡上搜集材料，分析整理，不只是學成語，探究能力也得到提高。對成語的梳理探究，是讓學生做一件很具體的事——梳理、分析、歸類。重在過程，重在課外、課前學生的工作。這樣的教學設計很有價值，讓學生在活動中得到提高。2．開拓了學生的眼界。學生放眼各種報刊，從報刊中發(fā)現(xiàn)問題——大家都可能出錯。這樣一來學生的眼界變寬了，自信心增強了。3．對成語的理解、運用比過去深刻。讓學生從對一個個具體成語的理解入手，進而認識到以后用成語不能犯“望文生義”等錯誤，從個例上升到一般。4．讓學生知道以后自己運用成語應抱什么態(tài)度，用什么方法。別人錯用成語，是前車之鑒。
人教版高中歷史必修2世界經(jīng)濟的區(qū)域集團化教案2篇
1、知識與能力：（1）了解歐洲聯(lián)盟的形成過程，剖析歐洲國家的一體化由經(jīng)濟實體向政治實體轉(zhuǎn)變的原因和實質(zhì)；（2）了解北美自由貿(mào)易區(qū)的形成過程，由北美自由貿(mào)易區(qū)的形成原因分析世界經(jīng)濟全球化與經(jīng)濟區(qū)域集團化之間的關系和影響。（3）了解亞太經(jīng)濟合作組織的形成過程，明確其特點及出現(xiàn)此特點的原因。掌握中國在加入該組織后所發(fā)揮的作用，并由此引申出中國在經(jīng)濟區(qū)域集團化過程中所發(fā)揮的作用。2、過程與方法：（1）通過學生對三大經(jīng)濟區(qū)域集團形成過程和特點的比較，鍛煉學生把具體的歷史現(xiàn)象與整體的社會背景聯(lián)系的能力，培養(yǎng)學生建立起全面的歷史觀。（2）通過對經(jīng)濟區(qū)域集團化趨勢的出現(xiàn)和它與經(jīng)濟全球化之間關系的分析，培養(yǎng)學生辨證的看問題，透過現(xiàn)象分析本質(zhì)的能力。
人教版高中政治必修3色彩斑斕的文化生活教案2篇
六、學習效果評價設計1、評價方式：我對學習效果的評價，來自兩個方面。一是教師的教授是否認真、嚴肅、科學；二是學生的學習成果如何，是否達成了事先預設的教學目標，是否在學習過程中有提高的過程。評價的方式有：同伴評價；教師自我評價和反思；學生反饋。2、評價量規(guī)：我設置了幾個問題用于課后的教學評價：（1）教學目標是否符合課標要求，是否符合三貼近原則，是否體現(xiàn)學生學習效果的生成性和過程性。（2）學習所用資源是否來自生活實際，是否真實，是否是學生感興趣的問題。（3）教師在課堂教學過程中是否能有效的通過提問和資料的展示分析，引導學生自己生成思考過程，而不是“教師代替學生的思考”。（4）學生參與的廣度和態(tài)度，學生是否提出有意義的觀點和問題。學生的回答是否是實話。
人教版高中語文必修3《文學作品的個性化解讀》教案2篇
教學目標：1、了解文學作品解讀的個性化及其原因。2、探討個性化解讀遵循的基本原則，合理解讀文學作品。教學重點：引導學生關注文學現(xiàn)象，培養(yǎng)他們對文學作品理解的多重思維能力。教學難點：把握個性化的度。避免偏激的理解、過度的張揚所謂個性，嚴重歪曲文學作品。教學方法：導讀、計論、合作探究。教學時間：一課時教學過程：一、創(chuàng)設情境、揭題導入：記得有這樣一個故事：一個小孩在四歲就能背《登鸛雀樓》，可平時只有在大人的要求下，他才背出來。直到六歲的某一天，他父母帶他去旅游，在他登陸上山頂時，竟然隨口背出：“欲窮千里目，更上一層樓”來。這說明了什么？……（討論）文學作品解讀的個性化。二、探討個性化解讀的原因1、讀者的差異導致解讀的個性化A、同一作品，閱讀的時間不同，解讀不同。如上面的例子。如《從百草園到三味書屋》和《風箏》主題的多元化理解?！皽毓手隆?，名作重讀，不但有趣，而且有益。B、同一作品，不同讀者，解讀不同。
人教版高中歷史必修1世界多極化趨勢的出現(xiàn)教案2篇
一、 教學目標 （一）知識與能力通過了解多極化趨勢和對世界的影響、歐盟的形成和擴展、日本成為經(jīng)濟大國的過程和原因、中國和第三世界的崛起等基本史實，培養(yǎng)學生綜合探究和歸納知識的能力（二）過程與方法以合作學習的“創(chuàng)設情境—目標顯示—自學嘗試—合作學習—成果匯報—總結評價”模式為主線，以學生自主探究活動為主體，以教師點撥為主導，以培養(yǎng)學生學習的興趣和能力為中心，來優(yōu)化課堂教學。教師創(chuàng)設重大國際事件的情境，讓學生親自探索各個主要國家對朝鮮戰(zhàn)爭和伊拉克戰(zhàn)爭立場和態(tài)度的決策，培養(yǎng)學生解讀歷史信息能力，并能夠根據(jù)自身的實際情況和外部環(huán)境，正確應對重大事件。 （三）情感態(tài)度與價值觀提高學生對二戰(zhàn)后美蘇兩極以外的各種政治經(jīng)濟力量增長的認識，初步理解世界多極化趨勢的形成及影響，樹立世界走向多極化是不可阻擋的歷史潮流的價值判斷標準。
人教版新課標高中物理必修2生活中的圓周運動教案2篇
思考：洗衣機脫水時轉(zhuǎn)速高時容易甩干衣物，還是轉(zhuǎn)速低時容易甩干衣物？(2) 制作棉花糖的原理內(nèi)筒與洗衣機的脫水筒相似，里面加入白砂糖，加熱使糖熔化成糖汁。內(nèi)筒高速旋轉(zhuǎn)，黏稠的糖汁就做離心運動，從內(nèi)筒壁的小孔飛散出去，成為絲狀到達溫度較低的外筒，并迅速冷卻凝固，變得纖細雪白，像一團團棉花。5.離心現(xiàn)象的防止在水平公路上行駛的汽車，轉(zhuǎn)彎時所需的向心力是由車輪與路面的靜摩擦力提供的。如果轉(zhuǎn)彎時速度過大，所需向心力F大于最大靜摩擦力Fmax，汽車將做離心運動而造成交通事故。因此，在公路彎道處，車輛行駛不允許超過規(guī)定的速度。當高速轉(zhuǎn)動的砂輪或者飛輪內(nèi)部分子間相互作用力不足以提供所需向心力時，離心運動就會使他們破裂，甚至釀成事故。