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人教版新課標(biāo)高中物理必修2平拋運(yùn)動教案2篇
（五）平拋運(yùn)動規(guī)律的應(yīng)用例1：一架老式飛機(jī)在高出海面45m的高處，以80m/s的速度水平飛行，為了使飛機(jī)上投下的炸彈落在停在海面上的敵船，應(yīng)該在與轟炸目標(biāo)的水平距離為多遠(yuǎn)的地方投彈?不計(jì)空氣阻力。分析：對于這道題我們可以從以下幾個方面來考慮：(1)從水平飛行的飛機(jī)上投下的炸彈，做什么運(yùn)動?為什么?(2)炸彈的這種運(yùn)動可分解為哪兩個什么樣的分運(yùn)動?3)要想使炸彈投到指定的目標(biāo)處，你認(rèn)為炸彈落地前在水平方向通過的距離與投彈時飛機(jī)離目標(biāo)的水平距離之間有什么關(guān)系?拓展：1、式飛機(jī)在高出海面45m的高處，以80m/s的速度水平飛行，尾追一艘以15m/s逃逸的敵船，為了使飛機(jī)上投下的炸彈正好擊中敵船，應(yīng)該在與轟炸目標(biāo)的水平距離為多遠(yuǎn)的地方投彈?不計(jì)空氣阻力。2、在一次摩托車跨越壕溝的表演中，摩托車從壕溝的一側(cè)以速度v＝40m/s沿水平方向向另一側(cè)，壕溝兩側(cè)的高度及寬度如圖所示，摩托車可看做質(zhì)點(diǎn)，不計(jì)空氣阻力。（1）判斷摩托車能否跨越壕溝？請計(jì)算說明（2）若能跨過，求落地速度？
人教版新課標(biāo)高中物理必修2向心力教案2篇
3．進(jìn)一步體會力是產(chǎn)生加速度的原因，并通過牛頓第二定律來理解勻速圓周運(yùn)動、變速圓周運(yùn)動及一般曲線運(yùn)動的各自特點(diǎn)。（三）、情感、態(tài)度與價值觀1．在實(shí)驗(yàn)中，培養(yǎng)學(xué)生動手、探究的習(xí)慣。2．體會實(shí)驗(yàn)的意義，感受成功的快樂，激發(fā)學(xué)生探究問題的熱情、樂于學(xué)習(xí)的品質(zhì)。教學(xué)重點(diǎn)1．體會牛頓第二定律在向心力上的應(yīng)用。2．明確向心力的意義、作用、公式及其變形，并經(jīng)行計(jì)算。教學(xué)難點(diǎn)1．對向心力的理解及來源的尋找。2．運(yùn)用向心力、向心加速度的知識解決圓周運(yùn)動問題。教學(xué)過程（一）、 引入新課：復(fù)習(xí)提問：勻速圓周運(yùn)動的物體的加速度——向心加速度，它的方向和大小有何特點(diǎn)呢？學(xué)生回答后進(jìn)一步引導(dǎo)：那做勻速圓周運(yùn)動物體的受力有什么特點(diǎn)呢？是什么力使物體做圓周運(yùn)動而不沿直線飛出？請同學(xué)們先閱讀教材
人教版高中語文必修2《采薇》教案2篇
這兩章是對戰(zhàn)爭場面的描寫。寫的是戰(zhàn)車、戰(zhàn)馬、象弭、魚服以及士兵的勞累奔波、饑渴難當(dāng)，通過這些具體生動的細(xì)節(jié)描寫來展現(xiàn)戰(zhàn)爭生活的圖景。而沒有寫戰(zhàn)場上的刀光劍影、廝打拼殺，但戰(zhàn)爭的殘酷已可想見。4“昔我往矣，楊柳依依。今我來思，雨雪霏霏”被視為情景交融的佳句。清人王夫之在論《詩經(jīng)·小雅·采薇》這兩句時說：“以樂景寫哀，以哀景寫樂，一倍增其哀樂?！闭?wù)勀愕目捶āＲ灰酝糁撘r眼前之實(shí)，以出征之樂襯內(nèi)心之思親之悲痛；二“楊柳依依”與“雨雪霏霏”對比，突出不勝今昔之感；三大雪交加，饑渴難當(dāng)，情境實(shí)悲，以哀景寫哀情。四、交流延伸1寫一首詩或一段文字表達(dá)你對“鄉(xiāng)愁”的新的體驗(yàn)。在全班交流。2課后搜集更多的表現(xiàn)鄉(xiāng)情的詩歌散文作品，將你最感動的一篇拿到班上與同學(xué)分享感受。
人教版高中語文必修2《涉江采芙蓉》教案2篇
三、想象畫面，把握意境1.指導(dǎo)想象學(xué)習(xí)陶淵明的《歸園田居》我們腦海中自然會出現(xiàn)一幅幅的畫面，比如他歸家后的生活場景，我們會想象“榆柳”是如何遮蔽房屋的，而“桃李”又是如何摘種在房前的。我們會想象村落是如何在薄霧中若隱若現(xiàn)的，想象炊煙是如何裊裊升起的?！渡娼绍饺亍芬辉娭挥?句話，更需要我們展開想象，去構(gòu)畫場景，這樣才能深入詩歌，體會到詩歌的味道。2.學(xué)生想象要求學(xué)生閉目想象1分鐘。3.學(xué)生展示想象結(jié)果（抽三四個學(xué)生回答即可）4.老師指導(dǎo)糾正學(xué)生想象不合理之處。要注意的地方：“江”可能學(xué)生會想象成小溪流、小池塘?！疤m澤”可能學(xué)生理解成“湖泊”。注意字詞“還顧”“漫浩浩”中隱含的情感，注意“離居”中流露的愁怨。5.時間允許的話，老師讀自己的下水作文。
人教版高中語文必修2《演講》教案2篇
一個世紀(jì)前，一位了不起的美國人簽署了奴隸解放宣言，而我們今天就站在他的塑像下面。對于千千萬萬身受不公正待遇之苦的黑奴來說，這份劃時代的文件，是一座光芒萬丈的希望燈塔，是結(jié)束他們被束縛之漫漫長夜的快樂黎明。我有一個夢，有朝一日在喬治亞州的丘陵地帶，奴隸的后代與奴隸主的后代，將能夠兄弟般地相處。我有一個夢，有朝一日甚至密西西比州，這個充滿不平與壓迫的州，將轉(zhuǎn)化成一片自由與公正的綠洲。我有一個夢，我的四個孩子，有朝一日將可以生活在這樣一個國度里：在此人們不是根據(jù)他們的膚色，而是根據(jù)他們的品行來衡量他們。我今天有一個夢！我有一個夢，有朝一日在阿拉巴馬州，盡管目前有許多惡毒的種族主義者，盡管州長叫嚷著要與聯(lián)邦政府對抗，有朝一日在阿拉巴馬州，黑人孩子與白人孩子將會像兄弟姊妹那樣親密無間。
人教版高中語文必修2《孔雀東南飛并序》教案2篇
讓學(xué)生仔細(xì)聆聽美妙的音樂，合作討論，加深理解。（1）本詩文中的“蘭芝被遣”和“蘭芝抗婚”的情節(jié)，可與樂曲展開部第一階段“逼嫁抗婚”對比閱讀。文中的劉蘭芝是在封建禮教的壓迫下被遣歸及被迫“改嫁”，劉蘭芝與祝英臺一樣都進(jìn)行了抗?fàn)?。樂曲中的樂器奏出了具有威脅力的封建勢力的主題，代表著封建勢力的兇暴殘酷，同時敘述了祝英臺的悲痛和不安心情，表現(xiàn)了控訴、抗?fàn)幍母星?。?）本詩文中的“夫妻誓別”的情節(jié)，可與樂曲呈示部中的結(jié)束部“長亭惜別”對比閱讀。文中劉蘭芝與焦仲卿的誓別。二人分手之際，依依不舍，“舉手長勞勞，二情同依依”。樂曲中梁祝分別時依依不舍又充滿悲傷，音調(diào)抒情徐緩。讓學(xué)生在徐緩的音樂中去感受劉蘭芝與焦仲卿生離死別的痛苦。
人教版高中語文必修2《故都的秋》教案2篇
三、具體研習(xí)1、文章的哪些段落描寫了故都的秋？郁達(dá)夫先生既然這么喜歡故都的秋，那么他選取了哪些畫面來寫故都的秋？（學(xué)生閱讀圈點(diǎn)，教師引導(dǎo)學(xué)生找關(guān)鍵詞、關(guān)鍵句。）明確：從3--11自然段。主要是5幅畫面，第３段庭院靜觀（破屋秋色），第４段槐樹落蕊（街頭落蕊），第５段秋蟬殘鳴，第６—10段閑話秋涼，第11段清秋佳果。2、故都的秋有什么特點(diǎn)？明確：清、靜、悲涼。2、作者在對這些景具體的描繪中，是如何體現(xiàn)故都秋“清、靜、悲涼”的特點(diǎn)的呢？（下面先請同學(xué)來誦讀課文3——11段落，其他同學(xué)要眼耳手腦并用，一是圈出文中體現(xiàn)秋天色彩的詞語，二是標(biāo)出傳遞聲響的物名。我們將從“秋色”和“秋聲”兩個角度來品味一下故都的“秋味”。）
人教版高中語文必修2《離騷》教案2篇
四、品味詩歌藝術(shù)1、詩人是如何表現(xiàn)其品質(zhì)的？運(yùn)用了什么修辭手法？產(chǎn)生了怎樣的表達(dá)效果？明確：詩句“扈江離與辟芷兮，紉秋蘭以為佩”很好地體現(xiàn)了詩人光輝俊潔的人格。用“江離”“辟芷”“秋蘭”三種香草來裝飾自己，比喻自己，極其生動形象地表現(xiàn)了詩人自己美好的精神世界，使詩歌充滿了浪漫主義氣息。2、《離騷》中作者常以“香草”、“美物”來比喻自己、賢士和君王，并表達(dá)政治理想，這是《離騷》的一大藝術(shù)特色，這種方法叫做“移情法”，即不直接說出自己想說的話，而是把它寄寓于某一物上，也就是“移情于物”，這種方法在古典詩詞中廣泛運(yùn)用，在政治不清明的時代，借用“移情”，可言難言之語，抒難抒之情。請找出相關(guān)的詩句，說說詩人是怎樣運(yùn)用這些比喻來表達(dá)政治理想的。
人教版新課標(biāo)高中物理必修2功率教案2篇
1．用CAI課件模擬汽車的啟動過程。師生共同討論：①如果作用在物體上的力為恒力，且物體以勻速運(yùn)動，則力對物體做功的功率保持不變。此情況下，任意一段時間內(nèi)的平均功率與任一瞬時的瞬時功率都是相同的。②很多動力機(jī)器通常有一個額定功率，且通常使其在額定功率狀態(tài)工作（如汽車），根據(jù)P=FV可知：當(dāng)路面阻力較小時，牽引力也小，速度大，即汽車可以跑得快些；當(dāng)路面阻力較大，或爬坡時，需要比較大的牽引力，速度必須小。這就是爬坡時汽車換低速擋的道理。③如果動力機(jī)器在實(shí)際功率小于額定功率的條件下工作，例如汽車剛剛起動后的一段時間內(nèi)，速度逐漸增大過程中，牽引力仍可增大，即F和v可以同時增大，但是這一情況應(yīng)以二者乘積等于額定功率為限度，即當(dāng)實(shí)際功率大于額定功率以后，這種情況不可能實(shí)現(xiàn)。
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(diǎn)，總結(jié)共同點(diǎn)。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 3 The Internet-Discovering Useful Structure教案一
This unit is about the Internet, which has a great influence to our humans and our lives. During the Listening & Speaking & Talking and Reading and Thinking section, the influence in examples has been shown. Thus, use the Present Perfect Tense is appropriate. However, in order to show the justice or weaken the doer of the behavior/action, it’s better to use the Present Perfect Passive Voice than the Present Perfect Tense. Besides, having learned to use the Present Perfect Passive Voice, students can beautify their language in their writing. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. Step 1 Observe the following sentences, then change the sentences into passive voice.He has been selected to take part in the sports meeting．(肯定句)他已被挑選出來參加運(yùn)動會。The ink has not been removed from his overcoat．(否定句)墨跡還沒有從他外套上去掉。
新人教版高中英語必修2Unit 3 The Internet-Listening &Speaking＆Talking教案二
From the pictures in the text and the title--- choose the best app, we can know that this part is about how to save money by using apps.Step 2 While-listening1. Laura and Xiao Bo are talking about apps. Listen to their conversation and find out what apps they want.Xiao Bo is looking for a(n) exercise app to help him get in shape.Laura would like an app for getting rich and another that will make her grades better.2. Listen again. Are the sentences true T or false F?1). Both of Xiao Bo's apps keep track of the steps he takes._____2). Xiao Bo's second app can help him make a fitness plan._____3). Laura needs an app that will help her get discounts.______4). Laura needs an app that will add money to her bank account._______F T F T3. Listen once more and tick the sentence you hear. Underline the words used to express predictions, guesses, and beliefs.Predictions, Guesses, and Beliefs________It might help me walk more.________My guess is that it wouldn't work.________I imagine this app would help me get fit faster________I suppose that would be good.________I guess you could save a little with this app.________I suppose there would be some problems, too.________I believe this app could help me get thinner.
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 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 3 The Internet-Listening &Speaking＆Talking教案一
Listening and Speaking introduces the topic of “ask about online habits”. Many middle school students have been surfing the Internet for many years, but what they do with the Internet and how much time they spend every day may not be very clear to themselves, nor to other students. This section allows students to investigate their peers' Internet use, which is conducive to their mutual understanding and understanding of the Internet. It can also help them reflect on their own online behavior, learn from other people's good online habits, and get rid of their bad online behavior.The listening text of this section is an investigation interview. The investigators interview specific groups with the same questions to obtain information, so as to understand their views, practices or attitudes on this issue. There are two specific questions: “how much time do you spend online every day? What do you usually do online?”. The answers of the three respondents provide rich and different information, and achieve the purpose of the investigators. The oral discourse structure of survey interviews generally includes greeting and explaining the purpose of the interview, presenting the interview questions and the respondents' answers. Listening and Talking introduces the theme of “choosing the right application ". Listening text is a conversation between Laura and Xiao Bo. In this part of listening, “oink”； “piggy bank” may cause the students' hearing comprehension limitation. Oink refers to sound word and pig's sound. So, add some oink to my piggy bank is often used to describe "making a little money".1. Guide students to understand the content of listening texts in terms of listening for definitions.2. Cultivate students' ability to define words and understand an investigation interview.
新人教版高中英語必修2Unit 3 The Internet-Reading and Thinking教案二
Q5：What's Jan's next goal?Her next goal is to start a charity website to raise money for children in poor countries.Q6：What can we learn from her experiences?We learn that when we go through tough times, we can find help and support from other people online. We learn that we can feel less lonelyStep 5: While reading---rethinkingQ1: What is Jan’s attitude to the Internet ?Thankful/Grateful, because it has changed her and her life.Q2: What writing skills is used in the article ?Examples(Jan’s example, the 59-year-old man’s and the 61-year-old woman’s example)Q3: Can you get the main idea of the article ?The Internet has changed Jan’s life/Jan’s life has been changed by the Internet.Step 6 Post reading---Retell the storyMuch has been written about the wonders of the World Wide Web. There are countless articles (1)telling(tell) us how the Internet has made our lives more convenient. But the Internet has done a lot (2)more(much) for people than simply make life more convenient. People’s lives (3) have been changed(change) by online communities and social networks so far. Take Jan for example, who developed a serious illness that made her (4)stuck(stick) at home with only her computer to keep (5)her(she) company. She joined an online group (6)where 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)benefits(benefit). She was so inspired (8)that 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)for children in poor countries. Jan’s life has been (10)greatly(great) improved by the Internet.
新人教版高中英語必修2Unit 3 The Internet-Reading For Writing教案一
⑦identity theft 身份盜竊⑧chat room 聊天室⑨draft your blog post 起草博客帖子⑩post embarrassing photos 張貼尷尬照片 【話題句式】 1. How do you stay safe online and avoid bad experiences on the Internet? 你如何在網(wǎng)上保持安全, 避免在網(wǎng)上的不良經(jīng)歷? 2. I’m not an expert, but many years as a blogger have taught me a thing or two. 我不是專家, 但作為一個博主, 我已經(jīng)學(xué)了好幾年了。 3. If you see or read something that makes you feel uncomfortable, leave the site immediately. 如果你看到或讀到一些讓你覺得不舒服的東西, 立即離開這個網(wǎng)站。4. Don’t give out your address or phone number. 別告訴別人你的地址或電話號碼。 5. Identity theft is a common and serious problem. 身份盜竊是一個常見而嚴(yán)重的問題。6. Being online is no excuse for being rude, and you don’t want to become a target for a troll or cyberbully. 上網(wǎng)并不是無禮的借口, 你也不想成為發(fā)挑釁帖子的人或網(wǎng)絡(luò)惡霸的目標(biāo)。 7. Trolls often use several false names so that they can stay on a site. 發(fā)挑釁帖子的人經(jīng)常使用幾個假名, 這樣他們就可以留在一個網(wǎng)站上。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。
人教版高中語文必修1《論語》教案2篇
【教學(xué)意圖】要了解中國傳統(tǒng)文化，必須閱讀古詩文名著名篇。但在中國文化形成過程中影響最大的是什么？可以說是儒家學(xué)說，包括《論語》這部經(jīng)典?！墩撜Z》等書是讀書人求仕做官的必修課本，是知識分子的思想言行基礎(chǔ)，而且影響到整個社會生活，內(nèi)容包括倫理道德、教育體制、民間習(xí)俗等方面的思想。因此，要了解中國傳統(tǒng)文化，有必要讀一讀《論語》?！窘虒W(xué)設(shè)計(jì)】因《論語》的年代已久遠(yuǎn)，對學(xué)生而言，要理解透徹文句是比較深奧困難的，因此必須在充分理解文意的基礎(chǔ)上，對《論語》進(jìn)行思想上的解讀?？捎山處煆摹墩撜Z》中概括出幾點(diǎn)與生活、現(xiàn)實(shí)相關(guān)的要點(diǎn)，要求學(xué)生分組進(jìn)行透徹的學(xué)習(xí)和領(lǐng)會，如“小人與君子”、“學(xué)習(xí)的方法”、“教育的理念”等等?！冀虒W(xué)重點(diǎn)、難點(diǎn)〗讀《論語》知儒家思想?！冀虒W(xué)方法〗講解啟發(fā)、探究梳理、拓展延伸。
人教版高中語文必修1《奇妙的對聯(lián)》教案2篇
3、介紹對聯(lián)的歷史引出本課的重點(diǎn)。人類歷史上的第一副對聯(lián)是“新年納余慶，嘉節(jié)號長春”。出現(xiàn)在五代十國時期（公元964年），距離現(xiàn)在已經(jīng)有1044年了。有著一千多年歷史的對聯(lián)有什么基本的特點(diǎn)呢？這是我們這節(jié)課學(xué)習(xí)的重點(diǎn)。請?jiān)谧母魑划?dāng)回醫(yī)生，給下面這幅對聯(lián)號號脈，看它對仗是否工整？上聯(lián)：冬去春來千條楊柳迎風(fēng)綠下聯(lián)：冰消雪化梅花萬朵撲鼻有什么問題，怎么改？剛才這幾位同學(xué)指出了這幅對聯(lián)的兩個問題，也提出了兩條修改意見。第一是下聯(lián)少了一個字，最好是添加一個“香”字；第二是下聯(lián)的“梅花萬朵”與上聯(lián)的“千條楊柳”是數(shù)量詞對名詞，名詞對數(shù)量詞，對仗不工整，要調(diào)整為“萬朵梅花”。這樣，數(shù)量詞“萬朵”對“千條”，名詞“梅花”對“楊柳”。大家還有沒有不同的看法。這樣我們就可以得出對聯(lián)的兩個特點(diǎn)特點(diǎn)：第一個特點(diǎn)是上下聯(lián)字?jǐn)?shù)要相等（板書）。就是上聯(lián)有幾個字，下聯(lián)也要有幾個字。大家記下來，對聯(lián)基本要求一，“上下聯(lián)字?jǐn)?shù)相等”。這個要求是很嚴(yán)格的，一般來說，違反這個規(guī)則就不成對聯(lián)了。
人教版新課標(biāo)高中物理必修1彈力教案2篇
一般情況下，凡是支持物對物體的支持力，都是支持物因發(fā)生形變而對物體產(chǎn)生彈力。所以支持力的方向總是垂直于支持面而指向被支持的物體。例1：放在水平桌面上的書書由于重力的作用而壓迫桌面，使書和桌面同時發(fā)生微小形變，要恢復(fù)原狀，對桌面產(chǎn)生垂直于桌面向下的彈力f1，這就是書對桌面的壓力；桌面由于發(fā)生微小的形變，對書產(chǎn)生垂直于書面向上的彈力f2，這就是桌面對書的支持力。學(xué)生分析：靜止地放在傾斜木板上的書，書對木板的壓力和木板對書的支持力。并畫出力的示意圖。結(jié)論：壓力、支持力都是彈力。壓力的方向總是垂直于支持面而指向被壓的物體，支持力的方向總是垂直于支持面而指向被支持的物體。引導(dǎo)學(xué)生分析靜止時，懸繩對重物的拉力及方向。引導(dǎo)得出：懸掛物由于重力的作用而拉緊懸繩，使重物、懸繩同時發(fā)生微小的形變。重物由于發(fā)生微小的形變，對懸繩產(chǎn)生豎直向下的彈力f1，這是物對繩的拉力；懸繩由于發(fā)生微小形變，對物產(chǎn)生豎直向上的彈力f2，這就是繩對物體的拉力。