-
人教版新課標高中物理必修1勻變速直線運動的速度與時間的關系教案2篇
一、設計思想通過本節(jié)教學，不但要使學生認識掌握勻變速直線運動的規(guī)律，而且要通過對這問題的研究，使學生了解和體會物理學研究問題的一個方法，圖象、公式、以及處理實驗數(shù)據(jù)的方法等。這一點可能對學生更為重要，要通過學習過程使學生有所體會。本節(jié)在內(nèi)容的安排順序上，既注意了科學系統(tǒng)，又注意學生的認識規(guī)律。講解問題從實際出發(fā)，盡量用上一節(jié)的實驗測量數(shù)據(jù)。運用圖象這種數(shù)學工具，相對強調(diào)了圖象的作用和要求。這是與以前教材不同的。在現(xiàn)代生產(chǎn)、生活中，圖象的運用隨處可見，無論學生將來從事何種工作，掌握最基本的應用圖象的知識，都是必須的。學生在初學時往往將數(shù)學和物理分割開來，不習慣或不會將已學過的數(shù)學工具用于物理當中。在教學中應多在這方面引導學生。本節(jié)就是一個較好的機會，將圖象及其物理意義聯(lián)系起來。
人教版新課標高中物理必修1用牛頓運動定律解決問題（二）教案2篇
觀察實驗視頻實驗驗證師：其實大家完全可以利用身邊的器材來驗證。實驗1、用彈簧秤掛上鉤碼，然后迅速上提和迅速下放。現(xiàn)象：在鉤碼被迅速上提的一瞬間，彈簧秤讀數(shù)突然變大；在鉤碼被迅速下放的一瞬間，彈簧秤讀數(shù)突然變小。師：迅速上提時彈簧秤示數(shù)變大是超重還是失重？迅速下放時彈簧秤示數(shù)變小是超重還是失重？生：迅速上提超重，迅速下放失重。體會為何用彈簧秤測物體重力時要保證在豎直方向且保持靜止或勻速實驗2、學生站在醫(yī)用體重計上，觀察下蹲和站起時秤的示數(shù)如何變化？在實驗前先讓同學們理論思考示數(shù)會如何變化再去驗證，最后再思考。（1）在上升過程中可分為兩個階段：加速上升、減速上升；下蹲過程中也可分為兩個階段：加速下降、減速下降。（2）當學生加速上升和減速下降時會出現(xiàn)超重現(xiàn)象；當學生加速下降和減速上升時會出現(xiàn)失重現(xiàn)象；（3）出現(xiàn)超重現(xiàn)象時加速度方向向上，出現(xiàn)失重現(xiàn)象時加速度方向向下。完全失重
人教版新課標高中物理必修1勻變速直線運動的位移與時間的關系教案2篇
一、教學目標1．知識與技能：(1)知道勻速直線運動的位移x＝υt對應著 圖象中的矩形面積．(2)掌握勻變速直線運動的位移與時間關系的公式 ,及其簡單應用．(3)掌握勻變速直線運動的位移與速度關系的公式 ,及其簡單應用．2．過程與方法：(1)讓學生初步了解探究學習的方法．(2)培養(yǎng)學生運用數(shù)學知識-----函數(shù)圖象的能力．(3)培養(yǎng)學生運用已知結論正確類比推理的能力．3．情感態(tài)度與價值觀：(1)培養(yǎng)學生認真嚴謹?shù)目茖W分析問題的品質(zhì)．(2)從知識是相互關聯(lián)、相互補充的思想中，培養(yǎng)學生建立事物是相互聯(lián)系的唯物主義觀點．(3)培養(yǎng)學生應用物理知識解決實際問題的能力．二、教學重點、難點1．教學重點及其教學策略：重點：(1)勻變速直線運動的位移與時間關系的公式 及其應用．(2)勻變速直線運動的位移與速度關系的公式 及其應用．教學策略：通過思考討論和實例分析來加深理解．
人教版新課標高中物理必修1用牛頓運動定律解決問題（一）教案2篇
（四）實例探究☆力和運動的關系1、一個物體放在光滑水平面上，初速為零，先對物體施加一向東的恒力F，歷時1秒，隨即把此力改變?yōu)橄蛭鳎笮〔蛔?，歷時1秒鐘，接著又把此力改為向東，大小不變，歷時1秒鐘，如此反復只改變力的方向，共歷時1分鐘，在此1分鐘內(nèi)A．物體時而向東運動，時而向西運動，在1分鐘末靜止于初始位置之東B．物體時而向東運動，時而向西運動，在1分鐘末靜止于初始位置C．物體時而向東運動，時而向西運動，在1分鐘末繼續(xù)向東運動D．物體一直向東運動，從不向西運動，在1分鐘末靜止于初始位置之東☆牛頓運動定律的應用2、用30N的水平外力F，拉一靜止放在光滑的水平面上質(zhì)量為20kg的物體，力F作用3秒后消失，則第5秒末物體的速度和加速度分別是A．v=7.5m／s，a=l.5m／s2B．v=4.5m／s，a=l.5m／s2C．v=4.5m／s，a=0D．v=7.5m／s，a=0
人教版新課標高中物理必修1勻變速直線運動的速度與時間的關系教案2篇
一、設計思想通過本節(jié)教學，不但要使學生認識掌握勻變速直線運動的規(guī)律，而且要通過對這問題的研究，使學生了解和體會物理學研究問題的一個方法，圖象、公式、以及處理實驗數(shù)據(jù)的方法等。這一點可能對學生更為重要，要通過學習過程使學生有所體會。本節(jié)在內(nèi)容的安排順序上，既注意了科學系統(tǒng)，又注意學生的認識規(guī)律。講解問題從實際出發(fā)，盡量用上一節(jié)的實驗測量數(shù)據(jù)。運用圖象這種數(shù)學工具，相對強調(diào)了圖象的作用和要求。這是與以前教材不同的。在現(xiàn)代生產(chǎn)、生活中，圖象的運用隨處可見，無論學生將來從事何種工作，掌握最基本的應用圖象的知識，都是必須的。學生在初學時往往將數(shù)學和物理分割開來，不習慣或不會將已學過的數(shù)學工具用于物理當中。在教學中應多在這方面引導學生。本節(jié)就是一個較好的機會，將圖象及其物理意義聯(lián)系起來。
人教版新課標高中物理必修1勻變速直線運動的位移與時間的關系教案2篇
一、教學目標1．知識與技能：(1)知道勻速直線運動的位移x＝υt對應著 圖象中的矩形面積．(2)掌握勻變速直線運動的位移與時間關系的公式 ,及其簡單應用．(3)掌握勻變速直線運動的位移與速度關系的公式 ,及其簡單應用．2．過程與方法：(1)讓學生初步了解探究學習的方法．(2)培養(yǎng)學生運用數(shù)學知識-----函數(shù)圖象的能力．(3)培養(yǎng)學生運用已知結論正確類比推理的能力．3．情感態(tài)度與價值觀：(1)培養(yǎng)學生認真嚴謹?shù)目茖W分析問題的品質(zhì)．(2)從知識是相互關聯(lián)、相互補充的思想中，培養(yǎng)學生建立事物是相互聯(lián)系的唯物主義觀點．(3)培養(yǎng)學生應用物理知識解決實際問題的能力．二、教學重點、難點1．教學重點及其教學策略：重點：(1)勻變速直線運動的位移與時間關系的公式 及其應用．(2)勻變速直線運動的位移與速度關系的公式 及其應用．教學策略：通過思考討論和實例分析來加深理解．
必修一牛頓第一定律教案
(二)?過程與方法? 4.?觀察生活中的慣性現(xiàn)象，了解力和運動的關系? 5.?通過實驗加深對牛頓第一定律的理解? 6.?理解理想實驗是科學研究的重要方法? (三)?情感態(tài)度與價值觀? 7.?通過伽利略和亞里士多德對力和運動關系的不同認識，了解人類認識事物本質(zhì)的曲折性? 8.?感悟科學是人類進步的不竭動力
人教版高中地理必修2煤城焦作出路何在說課稿
分析過焦作市的地理概況和產(chǎn)業(yè)優(yōu)勢后，就需要針對由于資源枯竭所帶來的問題提出合理化的建議。既然是談經(jīng)濟轉(zhuǎn)型，就應該將話題的范圍明確在這一領域內(nèi)。通過材料3的相關內(nèi)容，我們了解到焦作市需要在產(chǎn)業(yè)結構調(diào)整、培育新的優(yōu)勢產(chǎn)業(yè)、增強綜合競爭力等三個整改方針上下功夫。因而引導學生針對優(yōu)勢與不足提出建議，以三個整改方針為基準，衡量建議的可行性是鍛煉學生解決此類問題的有效途徑。在此我將教會學生的是解決問題方法而非案例的內(nèi)容，正所謂“授之以魚，不如授之以漁”。接下來針對學生的建議和教材資料分析所羅列的10點整改思路，由學生自由發(fā)言提出看法，通過教師的指導和學生的討論，進而確定經(jīng)濟轉(zhuǎn)型建議的具體方案。最后注意將建議與產(chǎn)業(yè)優(yōu)勢相對照，看建議是否都是圍繞著產(chǎn)業(yè)優(yōu)勢而提出的，這樣做會加深學生的印象，通過建議和優(yōu)勢的對應關系，將不難找出此類問題的解題思路。
人教版高中歷史必修3宋明理學說課稿3篇
陸王心學與程朱理學相比有何異同？生 不同點：在理的內(nèi)涵上不同，程朱理學認為“理”是貫通于宇宙、人倫的客觀存在，是一種普遍的規(guī)律準則；陸王心學認為心即理，是“良知”，認為人心便是世界萬物的本原。方法上也有不同：前者向外追究，“格物致知”；后者向內(nèi)探求，“發(fā)明本心”以求理，克服私欲、回復良知。生 相同點：都提出了一個宇宙、社會、人生遵循的“理”。師 對。程朱理學是客觀唯心主義，陽明心學是主觀唯心主義。這兩者的分歧是理學范圍內(nèi)的分歧，其基本思想是一致的。師 宋明理學與漢唐以前的儒學比較，最大的特點在于批判地吸收了佛教哲學的思辨結構和道教的宇宙生成論，將儒家的倫理學說概括升華為哲學基本問題。其實質(zhì)是把佛、道“養(yǎng)性”“修身”引向儒家的“齊家”“治國”“平天下”，對儒家的綱常道德給予哲學論證，使之神圣化、絕對化、普遍化，以便深入人心，做到人人遵而行之。
人教版高中英語必修3Astronomy the science of the stars說課稿3篇
Step 2 Pre-listeningAfter students finish their discussion, I will show a picture of Newton and ask them: Who is him? What is he famous for? Could you find out some words to describe him? Maybe students will answer that he is genius for his finding of theGravitation, making a great contribution to the progress of human being. At that time I will show another two pictures of Einstein and Hawking, letting students guess who they are and write down their idea about the Gravitation. For I have arranged them to search more information about the gravity before this class, Students have beenfamiliar with the topic and will not be afraid about this abstract conception, which is helpful for their listening.Step 3 While-listeningIn this step, students will be required to listen the material for three times. The first and listening is extensive listening and the second and third listening is intensive listening. In the first time, They are required to listen a material including Part 1 and Part 2 and choose the best summary of the listening text. After they choose the right answer, They also need work in group to explain what is wrong with the others. Then I will make a conclusion that we should pay attention to the first paragraph and last paragraph and some keys to get the main idea. By doing this, their capacity of generalization will have a great improvement.Before the second listening, I will ask students to scan the blank on the power point quickly and ask them to note down some key words .Then ask them to listen to the Part 1again and fill the first column of the chart. Maybe some students just show the ideas of these three scientists an still can’t catch their development of gravity. Therefore, I will ask them to listen to Part 2 again and fill in the rest. After finish the listening, I will give them ten minutes to discuss with their partner. I will also guidethem to improve their answers when they discuss with others.
人教版高中英語必修3Festivals around the World說課稿3篇
Teaching plan for Unit 1 book3Good morning, teachers. It’s my great pleasure to be here because I can share my lesson with you and I can learn a lot from it. I’ll begin my lesson from the following four parts， the teaching material, the teaching methods, the studying methods and the teaching procedure.Firstly, let me talk about the teaching material. The content of my lesson is the reading passage festivals and celebrations of Unit 1 Festivals around the world. This passage is about festivals and celebrations. By studying this passage, we’ll enable the students to know that festivals exit everywhere, and many of festivals in different countries celebrate similar ideas. As we all know, the reading passage is the center of each unit. If the Ss can learn it well, it will be helpful to make the Ss learn the rest of this unit.After studying the teaching material, I think the teaching aims are as the followings:1. Knowledge aims:(1) The Ss can master the usage of the important words andexpressions.(2)The Ss can use the __________________ (grammar) in the proper situation.Make students know about the festivals all over the world and the detail of the festivals, such as origin, content, and the date of the holiday festivals.2. Ability aims:(1) Students can talk about festivals and celebrations in English(2) To improve the student’s reading ability, especially their skimming and scanning ability.3. Emotion aims:Make the Ss know about the foreign festivals, and respect other countries’ custom.Next, let’s come to the important points and the difficult points.The important point is how to make the Ss understand the text better and the difficult point is how can they talk about it. secondly， Teaching Methods:1. task-based Language Teaching2. Computer assisted language teaching.3. question-and–answer methodThirdly， Studying Methods:
人教版高中英語必修3The million pound bank note說課稿3篇
在接下來的細讀環(huán)節(jié)，我套用了高考對閱讀理解的考查方式設置了5個問題，分別為三個推理判斷題，一個細節(jié)題和一個主旨大意題。學生需要對文章的內(nèi)容進行分析、歸納、推理、猜測等高級思維活動才能做出正確的回答?！驹O計意圖】這一過程是對學生進行細讀的訓練，培養(yǎng)學生獲取特定信息和挖掘文章深層次信息的能力。第三環(huán)節(jié):Intensive-reading (精讀) 15′第三個環(huán)節(jié)精讀，既是最重要的環(huán)節(jié)，也是突破本課重難點的關鍵。首先，讓學生思考劇本中人物看到百萬英鎊前后的態(tài)度發(fā)生了怎樣的變化。其次，讓學生仔細閱讀文章，找出可以表現(xiàn)人物態(tài)度變化的具體的語言和動作。最后，讓學生總結人物的態(tài)度發(fā)生變化的根本原因是什么，從而引出Money Talks, 供學生思考。【設計意圖】通過一系列的活動培養(yǎng)學生學習從人物的語言和動作探究人物的心理，使學生進一步體會戲劇語言的魅力，從而對文章背后所反映的社會問題進行思考，也為下一步的討論環(huán)節(jié)做好鋪墊。
人教版高中歷史必修2古代的經(jīng)濟政策說課稿
3、清代的“閉關鎖國”政策：（1）原因：①根本原因：自給自足的封建自然經(jīng)濟；②客觀原因：西方殖民者向東方殖民擴張；③直接原因：對付東南沿海人民的抗清斗爭（2）內(nèi)容：嚴格限制對外貿(mào)易。但并不是禁絕海外貿(mào)易。康熙晚期，禁止商人前往南洋貿(mào)易；乾隆時只開廣州一處通商，并設立政府特許的貿(mào)易機構廣州“十三行”統(tǒng)一經(jīng)營管理對外貿(mào)易。（3）后果：①閉關鎖國政策妨礙了海外市場的開拓，抑制了資本的原始積累，從而阻礙了資本主義萌芽的發(fā)展。②閉關鎖國政策隔絕了中國與外界的聯(lián)系，從而阻斷了中國學習西方的先進科學技術，阻礙了生產(chǎn)力發(fā)展，使中國落后于世界潮流。③“閉關鎖國”政策在一定程度上也保護了國家的安全。教師可以設置問題：17-18世紀中國顯露出哪些危機？
新人教版高中英語必修3Unit 2 Morals and Virtues教學設計二
Activity 41. Students complete the task of activity 4, then teachers and students check the answers. 2. The teacher organized the students to work together and asked them to use the tables and mind maps sorted out before to retold the important choices in Lin Qiaozhi's life and their resultsStep 5 Language points1. The teacher asks the students to read the text carefully, find out the core words and long and difficult sentences in the text and draw lines, understand the use of vocabulary, and analyze the structure of long and difficult sentences. 2. The teacher explains and summarizes the usage of core vocabulary and asks the students to take notes. 3. The teacher analyzes and explains the long and difficult sentences that the students don't understand, so that the students can understand them better. Step 6 Homework1. Read the text again, in-depth understanding of the text; 2. Master the use of core vocabulary and understand the long and difficult sentences. 3. Complete relevant exercises in the guide plan. 1、通過本節(jié)內(nèi)容學習，學生是否理解和掌握閱讀文本中的新詞匯的意義與用法；2、通過本節(jié)內(nèi)容學習，學生能否結合文本特點總結林巧稚的人生原則和人格品質(zhì)特征；3、通過本節(jié)內(nèi)容學習，學生能否針對人生抉擇發(fā)表自己的看法；能否全面地、客觀地、理性地看待問題，進而對道德和人性有更加深入的思考和理解。
新人教版高中英語必修3Unit 2 Morals and Virtues教學設計三
The joke set her crying.這個玩笑使她哭起來。Step 5 ReadingActivity 31. Students read the small text in activity 3. The teacher provides several small questions to check whether students understand the content of the text and the ideographic function of the -ing form in the text.*Where are those people?*Why did Dr Bethune come to China?*How did he help the Chinese people during the war?*What did Chairman Mao Zedong say about him?2. Ss try to rewrite some sentences using the -ing form. Then check the answers. When checking the answers, the teacher can ask different students to read the rewritten sentences and give comments.Answers:1. he became very interested in medicine, deciding to become a doctor.2. …after hearing that many people were dying in the war.3. Helping to organise hospitals, he taught doctors and nurses, and showed people how to give first aid./ He helped to organise hospitals, teaching doctors and nurses, and showing people how to give first aid.4. …praising Dr Bethune as a hero to be remembered in China.Step 6 PracticeActivity 4Students complete grammar activities 2 and 3 on page 69 of the workbook.Step 6 Homework1. Understand and master the functions and usage of the -ing form;2. Finish the other exercises in Using structures.1、通過本節(jié)內(nèi)容學習，學生是否理解和掌握動詞-ing形式作賓語補足語語和狀語語的功能和意義；2、通過本節(jié)內(nèi)容學習，學生能否正確使用動詞-ing形式描述人物的行為、動作及其經(jīng)歷；3、通過本節(jié)內(nèi)容學習，學生能否獨立完成練習冊和導學案中的相關練習。
新人教版高中英語必修3Unit 2 Morals and Virtues教學設計四
3.Teachers ask different groups to report the answers to the questions and ask them to try different sentence patterns.The teacher added some sentence patterns for students to refer to when writing.Step 4 Writing taskActivity 51.Write the first draft.Students first review the evaluation criteria in activity 5, and then independently complete the draft according to the outline of activity 4, the answers to the questions listed in the group discussion and report, and the reference sentence pattern.2.Change partners.The teacher guides the students to evaluate their partner's composition according to the checklist of activity 5 and proposes Suggestions for modification.3.Finalize the draft.Based on the peer evaluation, students revise their own compositions and determine the final draft.Finally, through group recommendation, the teacher selects excellent compositions for projection display or reading aloud in class, and gives comments and Suggestions.Step 5 Showing writingActivity 5T call some Ss to share their writing.Step 6 Homework1. Read the passage in this section to better understand the passage.2. Carefully understand the hierarchical structure of the article, and deeply understand the plot of the story according to the causes, process and results;3. Independently complete the relevant exercises in the guide plan.1、通過本節(jié)內(nèi)容學習，學生是否理解和掌握閱讀文本中的新詞匯的意義與用法；2、通過本節(jié)內(nèi)容學習，學生能否通過人物言行的對比分析道德故事的深層內(nèi)涵；3、通過本節(jié)內(nèi)容學習，學生能否根據(jù)故事的起因、經(jīng)過和結果來深入理解故事的情節(jié)，從而了解文章的層次結構；4、結合現(xiàn)實生活案例發(fā)表自己的見解和看法,寫一篇觀點明確、層次分明的故事評論。
新人教版高中英語必修3Unit 2 Morals and virtues教學設計一
(2) students are divided into groups according to the requirements of activity 3. Each student shares a story of personal experience or hearing-witnessing kindness, and then selects the most touching story in the group and shares it with the whole class. Before the students share the story, the teacher can instruct them to use the words and sentence patterns in the box to express. For example, the words in the box can be classified:Time order: first of all, then, after that, later, finally logical relationship :so, however, although, butTeachers can also appropriately add some transitional language to enrich students' expression:Afterwards, afterwards, at last, in the end, eventuallySpatial order: next to, far from, on the left, in front ofOtherwise, nevertheless, as a result, therefore, furthermore, in addition, as well asSummary: in a word, in short, on the whole, to sum up, in briefStep 8 Homework1. Understand the definition of "moral dilemma" and establish a correct moral view;2. Accumulate vocabulary about attitudes and emotions in listening texts and use them to express your own views;3. Complete relevant exercises in the guide plan.1、通過本節(jié)內(nèi)容學習，學生能否理解理解“道德困境”的定義；2、通過本節(jié)內(nèi)容學習，學生能否通過說話人所表達的內(nèi)容、說話的語氣、語調(diào)等來判斷其態(tài)度和情緒；3、通過本節(jié)內(nèi)容學習，學生能否針對具體的道德困境發(fā)表自己的看法和見解，能否掌握聽力理訓練中的聽力策略。
人教版高中英語必修2Cultural Relics說課稿2篇
Ⅲ. Analysis of the teaching material:The topic of this unit is cultural relics. Students are quite interested in topics about different cultures around the world. This is the second period of the whole unit. As a reading class, the passage mainly talks about the history of the amber room (how it was made, sent as a gift, lost and rebuilt).According to the new national curriculum, when teaching reading, much emphasis should be put on training the students’ reading skills.Ⅳ. Teaching objectives1. Language objectives:1) Students are required to master the key words and phrases occurred in the passage (e.g. amazing, decorate, belong, in return, less than etc.)2) Students are required to learn the attributive clause and acquire the sentence pattern.2. 1) Students are required to describe a certain thing by using the new sentence patterns.2) Students are required to master two kinds of reading skills—skimming and scanning, and learn to use them in their daily reading.3. 1) Students are required to know the history of the amber room.2) Students are required to appreciate cultural relics and understand the importance of protecting them.Ⅴ. Teaching important and difficult points1) the new words, phrases, and sentence pattern in the course of reading.2) Teaching difficult point: Help the students master two kinds of reading skills—skimmingand scanning and learn to apply them in daily use.Ⅵ. Teaching methods:Task-based method & Top-down model Ⅶ. Teaching aids: PPT, pictures, blackboard Ⅷ. Teaching procedure:
人教版高中英語必修2The Olympic Games說課稿2篇
Purpose of my design:To ask the students to do these two tasks will make the Ss predict the story of this passage. As a result, it will deepen Ss’ memory of this story because they will have their own understanding of this story.Step 3. While-readingTask 1. (Individual work _____min)Skimming: ask students to skim the text and the main ideas of each paragraph in this passage. Please read it quickly and then match the sentences with the letters.Task 2. (Individual work _____min)Scanning: read the text quickly and decide the whether the following statements are true or false and give reasons.Task 3. (Pair work _____min)Listen to the tape and fill in the banks. Then read the paragraph with expression to your partner.Task4 (individual work min)Listen to the tape again and write down the main idea in one sentence.Purpose of my design: Enable students to understand the given material better by using different reading skills. And proper competition can arouse the Ss’ interest in English learning. “Task-based” teaching method is used here todevelop the Ss’ ability of communication and also their ability of co-operation will be well trainedStep 4. Post-readingTask 1. (Individual work, pair work, group work, class work; _____min)Discussion (group of 4):1. If you were Hippomenes, would you run against Atlanta?2. Do you think Hippomenes deserved to win the race? Why or why not?Step 5. HomeworkPlease read the story again carefully after class and imagine: What will happen during the race between Hippomenes and Atlanta? Who do you think will win the race? Do you think Atlanta would marry Hippomenes? Write an end for the story with thses questions.Purpose of my design: Homework is so important and necessary for to master the knowledge they learned after class. It will check whether the Ss achieve the teaching aims.Part 5 Blackboard design
人教版新課標高中物理必修2功率說課稿2篇
（一）、復習提問1、請說出功的計算公式及功的單位2、我們用哪個物理量表示物體運動的快慢？（二）、創(chuàng)設情景，引入新課1、播放多媒體素材，用起重機和一個工人搬運幾百塊磚比較哪一種方法好？圖中的情景說明了什么問題?（教師通過所設計的情景，將學生引入怎樣比較做功快慢，讓學生發(fā)表自己的看法，初步知道物體做功是有快慢之分的。）（三）、進行新課1、比較做功快慢的方法播放多媒體素材并提出問題：怎樣比較兩個人誰做功快誰做功慢？教師啟發(fā)：以前學習過要比較兩物體運動的快慢，可以先確定路程再比較時間，也可以先確定時間再比較路程。在路程和時間都不同時，通過計算速度比較兩物體運動的快慢。同理，要比較物體做功的快慢可采用什么方法？
