Good afternoon, teachers, It’s my great pleasure to be here sharing my lesson with you.The content of my lesson is Senior English Book 3 Unit 5 Canada —— “The true North”.I’ll be ready to begin this lesson from five parts. Analysis of the teaching material,the teaching methods,the studying methods, the teaching procedure,and Blackboard design.First, let me talk about the teaching material.Part 1 Teaching Material:This unit is about the introduction of Canada. By studying of this unit,we’ll enable the students to learn the geography, population, main cities, and natural beauty, natural resources of Canada. Through the training of the unit, it also requires students to learn some Language skills such as the expressions of position and emotions.So it plays an important part in the English teaching in this book.After studying the teaching material and analyzing the rule of children’s growing of mind,I think the teaching aims are the followings:1.Knowledge objects:(1) make the students learn some new words and phrases(2) make the students understand the content of the lesson.2.Ability objects:(1)To develop the Ss’ abilities of listening, speaking, reading and writing. Especially reading and speaking ability.(2) learn to talk about the characters of Canada in English(3)To train the Ss’ ability of working in pairs.3.Emotion objects:(1)Enable students to understand the characters of Canada..(2)Stimulate Ss to work hard to make China stronger.Part 2 Teaching Methods:I think helping students learn to master new words and phrases and improve the students’ reading and speaking ability is import and the difficult.According to the analysis of the teaching material and the import points and the difficult points,I will use the following teaching methods : question-guiding approach; fast-reading and careful reading; multi-media teaching methods; discussion
The oldest and the most popular park in the worldenjoy the exciting activities thereget close to the life-size cartoon characters like Mickey Mouse and Donald Duck Step 3 Pre-reading1.What do you suppose a theme park is ?2.What do you think you can see in a theme park?(1.It is a kind of amusement park which has a certain theme – that the whole park is based on. 2.buildings, castles, statues, rare animals and birds, and so on.) Step 4 Reading ----- Theme Parks –---- Fun and More Than Fun1.Predict : Read the title and the pictures on P. 34 and PredictWhat is the meaning of the title “Theme Park – Fun and more than fun”?(The title means that theme parks are fun to visit, but that they can also be educational and can offer useful information.)2.Skimming Fast read and answer:What activities can we take in a theme park?Amusement park: Bumper car Merry-go-round slide bungee jumping Free-fall rides Horror films Pirate ship Ferris wheel roller coaster3.Scanning Read again and you will find various theme parks are mentioned in the passage . Then what are they ?Theme parks: Sports theme park History theme park Culture theme park Marine or Ocean theme Park Future park Science theme park Disneyland4.Careful reading and find the main idea of each paragraph:THEME PARKS---- entertaining/ educationalPara.1 Traditional parks are places to go for relaxation and to have time away from our busy lives.Para.2 Theme parks are different They’re large and full of things to do, see and buy.Para.3 Theme parks are built around a single idea or theme. One example is a sports park.Para.4 Another kind of theme park is historical more and cultural and can be educational.Para.5 Disneylandwas the first theme park. It is based on the fantasy life and characters of Disney’s films.Para.6 Some examples of educational theme parks include sea world parks and science parks.
Language learning needs a context, which can help the learners to understand the language and then can product comprehensible output, so computer has the advantages to make the materials attractive.Part 3 Learning MethodsTask-based, self-dependent and cooperative learningPart 4 Teaching ProcedureStep One Lead-in“Interest is the best teacher.” Therefore, at the very beginning of the class, I should spark the students’ mind to focus on the centre topic “the band”. I’ll show some pictures of food to attract their attention and then bring some questions.Question:What kind of food they like?What should go into a good meal?The answers must relate to the diet. After this, the students will be eager to know something about a balance diet and this is the very time to naturally lead the class into Step 2Step 2 Reading for information: skimming and scanning In this step, I use Task-based Language Teaching method, which can give students a clear and specific purpose while skimming and scanning the context.Task 1 General ideaThe students will be asked to just glance at the title and the pictures of the passage, and then guess what they will read in the text. And they’ll be divided into groups of four to have a discussion.The purpose is to inspire the students to read actively, not passively. In addition, the task is to develop the students’ reading skill by making prediction and to encourage the students to express their thoughts in English and cooperate with each other.Task 2 Main idea of each paragraphCooperative learning can raise the students’ interest and create an atmosphere of achievement. Based on this theory, I divide the whole class into 4 groups to skim the whole text and get the main idea of each paragraph.
Knowledge objectives:(1) to make Ss grasp the usage of words, expressions and sentence structures: statistics, struggle, thanks to, rid of, some patterns for persuasion, the “ing” form as subject and object;(2)to use learnt knowledge to persuade sb.Ability objectives:(1) to develop Ss’ reading skills(skimming, scanning, word guessing);(2) to improve Ss’ speaking, communicating and cooperating skills.Emotional objectives:to make Ss know the contribution of Yuan,and learn his spirit and his simple life time.Teaching important and difficult points:(1) some words, expressions and sentence structures mentioned above;(2)the content of the text;(3)training their reading and speaking skills.Teaching methods: CLT, TBLT,QT.Learning strategies: CLS, QLS, TBLS.Teaching procedures:Step 1 lead-in: (1) teacher plays a piece of recent news from CCTV about the harvest of the super hybrid rice, and ask students whether they know Yuan or not, and talk about him and his contribution.(2)Brain storm: let Ss describe Yuan in their minds including his appearance, his living condition and so on.Step 2 fast reading tasks:(1)teacher introduces Yuan and super hybrid rice(2)make Ss read the text as fast as possible with questions. Such as: what’s the general ideaof this passage? What’s Yuan’ dream? (skimming and scanning skill)Step 3 intensive reading tasks(1)let Ss read the text silently, find topic sentence of each paragraph and draw the difficult sentences and the knowledge what they don’t understand.(words guessing)(2)teacher and Ss talk about the important words, expressions and sentences together, and ask Ss to retell the content of the text.(summarizing and paraphrasing)(3)teacher summarize this part.(4) read again following the courseware.
一、教材分析1、教學(xué)對象分析《再別康橋》的教學(xué)對象是高一學(xué)生,高一學(xué)生往往對那種純粹的、原始的、本真的情感體會較為膚淺,《再別康橋》是新月派詩人徐志摩的傳世之作,有極高美學(xué)價(jià)值,它所抒發(fā)的離愁別緒是人類共同的情感經(jīng)歷,通過誦讀容易將學(xué)生帶人詩境,喚醒他們沉寂的真情,從而引起強(qiáng)烈的共鳴。 2、教材地位及作用 高中語文第一冊第一單元為詩歌單元,本單元收錄了中國現(xiàn)當(dāng)代的一些優(yōu)秀詩篇?!对賱e康橋》安排在本單元的第二課,屬于必讀課。雖然本詩向來眾說紛紜,但其藝術(shù)之美人所共知,培養(yǎng)學(xué)生高尚的審美情趣和良好的審美創(chuàng)造力是語文學(xué)科的任務(wù),因此,從語言賞析入手,從情感體驗(yàn)切入,就可以讓學(xué)生通過學(xué)習(xí)本課體會現(xiàn)代詩歌的特點(diǎn),多方面感受體悟詩歌的情感,受到美的熏陶。
(一)解題:包身工──舊社會一種變相的販賣奴隸的形式。被販賣的多是女孩子由承辦人送到工廠做工,無人身自由,所得工資全部歸承辦人所有,在這種形式下做工的人也稱包身工。包身工是指二三十年代(時(shí)間),在上海東洋紗廠里(地點(diǎn)),為外國人工作的女工(工作性質(zhì))。因?yàn)檫@些女工在進(jìn)廠時(shí)已經(jīng)簽訂了賣身契,失去了人身的自由權(quán),所以被稱為“包身工”。標(biāo)題中的“包身”二字,突出了帝國主義、封建勢力對中國女童工的殘酷剝削的罪行,控訴了他們的野蠻殘暴的統(tǒng)治手段,以激起人們的義憤和同情,這是全文的中心思想。(二)關(guān)于報(bào)告文學(xué):《包身工》屬于報(bào)告文學(xué)。(同類題材有初中的《地質(zhì)之光》、《誰是最可愛的人》)報(bào)告文學(xué),是文學(xué)體裁的一種,散文的一類,是文藝通訊、速寫、特寫的總稱,是文學(xué)創(chuàng)作中的“輕騎兵”。
4、本文的重點(diǎn)是說辭,雖僅百余字,卻委婉曲折,步步進(jìn)逼,層層深入,表現(xiàn)出高超的勸說藝術(shù)、游說技巧。讓學(xué)生細(xì)細(xì)品味并概括說辭中包含幾層意思。第一層(“秦、晉圍鄭,鄭既知亡矣”),分析形勢,以退為進(jìn),博得好感。第二層(“若亡鄭而有益于君”至“君之薄也”),亡鄭陪鄰,動(dòng)搖聯(lián)盟。第三層(“若舍鄭以為東道主”至“君亦無所害”),存鄭有益,利益引誘。第四層(“且君嘗為晉君賜矣”至“唯君圖之”),追溯歷史,深入離間??梢姞T之武面對大國的君主,巧舌如簧,不卑不亢,從容辭令,既不刺激對方也不失本國尊嚴(yán),語言的分寸掌握得恰到好處。表現(xiàn)出燭之武機(jī)智善辯的外交才能。5、面對風(fēng)云突變的局勢,晉侯沒有感情用事,而表現(xiàn)了清醒的頭腦和理智的判斷。這種隱忍不發(fā)、隨機(jī)應(yīng)變的胸懷和謀略,正是晉文公終成霸業(yè)的根本原因。設(shè)計(jì)意圖:本環(huán)節(jié)的重點(diǎn)是全面把握燭之武這一人物性格特征,以及退秦師過程中體現(xiàn)出的非凡的膽識以及高超的謀略和語言藝術(shù)。
(4)Finally, I will ask the SS what this sentence mean:It is always calm before a storm.Purpose: attract the SS attention and bring them into discussionStep 2: Pre-reading 讀前Here, I will do the second question in pre-reading first. I will use the method of brainstorming to ask the SS what will happen before an earthquake; and list the phenomenon on the table. 2. Then I will show the SS the picture of abnormal phenomenon, at the same time, encourage the SS to describe.3、finally, I will summarize these phenomenon4、Do the first question in the pre-reading , Imaging your home begins to shake and you must leave it right away. You have time to take only one thing. What will you take? Why?Purpose: help the SS to get further understanding of the topic and stimulate their interests.Step3: While-reading 閱讀(1). Skimming Read the text quickly and catch the meaning of the first and second sentence of each paragraph. Predict the meaning of new words(2).scanning(找讀)A. Read the text again. Do the following question.1. When and where were the strange things happening?2. What are they?3. Why did the text say the world seemed to be at an end?4. How was the city destroyed after the quake?5. When did the second quake hit the city? What was the result of that?6. Who came to help Tangshan first? And how?B. Work in pairs to discuss the question.
共享實(shí)驗(yàn)收集的信息,分享實(shí)驗(yàn)探究的結(jié)論,體驗(yàn)收獲的樂趣。 小結(jié)拓展 這節(jié)課由大家感興趣的球類運(yùn)動(dòng)和彈弓游戲,提出了功與速度變化關(guān)系的問題,利用倍增思想解決測量對物體做功的問題,使用我們熟悉的器材設(shè)計(jì)了探究方案,并進(jìn)行實(shí)驗(yàn)探究,采用圖像法進(jìn)行數(shù)據(jù)處理,初步得出W∝V2的關(guān)系。在我們這節(jié)課探究以前,科學(xué)家就通過試驗(yàn)和理論的方法,已經(jīng)總結(jié)出了功與速度變化的定量關(guān)系。人類社會也在社會生活和生產(chǎn)的各個(gè)領(lǐng)域予以利用。比如,古代的戰(zhàn)爭武器拋石器、大型弓弩,以及現(xiàn)代飛機(jī)彈射系統(tǒng)、還有機(jī)器人行走等等,希望同學(xué)在今后的學(xué)習(xí)中注意留心生活中的物理和社會中的物理。 領(lǐng)會總結(jié)。培養(yǎng)概括總結(jié)的能力,進(jìn)一步鞏固、感悟、提升實(shí)驗(yàn)探究中獲得的思維能力及動(dòng)手能力。感悟社會中的物理,認(rèn)識物理學(xué)對科技進(jìn)步以及文化和社會發(fā)展的影響。 列舉學(xué)生知道的社會中做功使物體速度變化的例子,增強(qiáng)學(xué)生將物理知識應(yīng)用于生活和生產(chǎn)的意識,培養(yǎng)學(xué)生的社會參與意識和對社會負(fù)責(zé)任的態(tài)度。
(5)高度不同,對平拋運(yùn)動(dòng)距離有何影響,是否因?yàn)楦叨葴p小后下落時(shí)間減小,所以要增大速度才能達(dá)到相同的距離?(教學(xué)實(shí)踐證明,這種想法在學(xué)生比較多見。已經(jīng)不自覺的沿用了自由落體運(yùn)動(dòng)的規(guī)律,又隱隱有運(yùn)動(dòng)等時(shí)性的痕跡。應(yīng)引導(dǎo)學(xué)生這一結(jié)果還需實(shí)驗(yàn)驗(yàn)證。)教師的引導(dǎo):其實(shí),我們所提出的看法都跟平拋運(yùn)動(dòng)的規(guī)律有關(guān)系。那么平拋運(yùn)動(dòng)究竟有怎樣的規(guī)律呢?以前學(xué)過的直線運(yùn)動(dòng)知識還能用于今天的內(nèi)容嗎?由此逐步使學(xué)生意識到分析平拋運(yùn)動(dòng)須采用運(yùn)動(dòng)合成與分解這一方法。三、實(shí)驗(yàn)驗(yàn)證自主探究(15分鐘) 物理是實(shí)驗(yàn)科學(xué),多媒體教學(xué)不能代替實(shí)驗(yàn)。本教學(xué)設(shè)計(jì)的第三個(gè)環(huán)節(jié)是實(shí)驗(yàn)驗(yàn)證,鼓勵(lì)學(xué)生自主探究。引導(dǎo)學(xué)生根據(jù)自己的猜想(實(shí)驗(yàn)?zāi)康模┰O(shè)計(jì)實(shí)驗(yàn)進(jìn)行驗(yàn)證。(1)介紹手持式平拋豎落儀,引導(dǎo)并小結(jié)實(shí)驗(yàn)要領(lǐng):聽兩小球下落聲音判斷其下落時(shí)間。體會合運(yùn)動(dòng)和分運(yùn)動(dòng)是等時(shí)的。
(四)、彈性勢能(據(jù)課時(shí)情況,可以讓學(xué)生自學(xué))生活中還有一些物體既沒有運(yùn)動(dòng)也沒有很大的高度卻同樣“儲存”著能量,哪怕它只是孩童手里的玩具(圖片:彈弓)。張緊的弓一撒手就會對箭支做功改變它的動(dòng)能,松弛的弓有這樣的本領(lǐng)嗎?同樣是弓前者具有能量而后者沒有,那么什么情況下物體才具有這種能量呢?張緊的弓在恢復(fù)原狀的過程會對外做功,但是拉斷的弓還能有做功的本領(lǐng)嗎?1.定義:物體由于發(fā)生彈性形變而具有的能量叫做彈性勢能。2.彈性勢能的大小與哪些因素有關(guān)呢?3、勢能由相互作用的物體的相對位置決定的能量。重力勢能:由地球和物體間相對位置決定。彈性勢能:由發(fā)生形變的各部分的相對位置決定。(五).反饋練習(xí)1. 物體在運(yùn)動(dòng)過程中,克服重力做功50J, 則( )A.重力做功為50JB.物體的重力勢能一定增加50JC.物體的重力勢能一定減少50JD.重力做功為-50J
1、舉例:2、結(jié)論:(1)物體的運(yùn)動(dòng)軌跡是曲線的運(yùn)動(dòng)叫曲線運(yùn)動(dòng)。(2)曲線運(yùn)動(dòng)中速度方向是時(shí)刻改變的。(二)、曲線運(yùn)動(dòng)方向:1、質(zhì)點(diǎn)在某一點(diǎn)(或某一時(shí)刻)的速度的方向是在曲線的這一點(diǎn)的切線方向。2、曲線運(yùn)動(dòng)中速度方向是時(shí)刻改變的,因此曲線運(yùn)動(dòng)是變速運(yùn)動(dòng)。(三)、曲線運(yùn)動(dòng)條件:1、演示實(shí)驗(yàn):2、結(jié)論:當(dāng)物體所受的合力的方向跟它的速度方向不在同一直線時(shí),物體就做曲線運(yùn)動(dòng)。七、課堂小結(jié):1、運(yùn)動(dòng)軌跡是曲線的運(yùn)動(dòng)叫曲線運(yùn)動(dòng)。2、曲線運(yùn)動(dòng)中速度的方向是時(shí)刻改變的,質(zhì)點(diǎn)在某一點(diǎn)的瞬時(shí)速度的方向在曲線的這一點(diǎn)的切線上。3、當(dāng)合外力F的方向與它的速度方向有一夾角a時(shí),物體做曲線運(yùn)動(dòng)。八、鞏固訓(xùn)練:1、關(guān)于曲線運(yùn)動(dòng),下列說法正確的是()。A:曲線運(yùn)動(dòng)一定是變速運(yùn)動(dòng);B:曲線運(yùn)動(dòng)速度的方向不斷的變化,但速度的大小可以不變;
學(xué)生中存在這樣的問題:既然宇宙間的一切物體都是相互吸引的,那么為什么沒有吸引到一起?為了解決這個(gè)問題,安排了例題2例2、兩物體質(zhì)量都是1kg,相距1m,它們間的萬有引力是多少?通過本題,讓學(xué)生認(rèn)識到一般物體間的引力極小,不用考慮。那么,質(zhì)量很大的天體為什么沒被吸引到一塊?從而引出下節(jié)課題。4.課堂小結(jié):本節(jié)課,從天體運(yùn)動(dòng)出發(fā),通過推理證明,形成理性認(rèn)識,再結(jié)合例題習(xí)題使學(xué)生的理性認(rèn)識再反饋到具體事實(shí)。形成實(shí)踐-理論-實(shí)踐的認(rèn)知循環(huán),順應(yīng)了認(rèn)知規(guī)律.。本共設(shè)計(jì)了很多問,能讓學(xué)生想的盡量讓學(xué)生想、能學(xué)生說的盡量讓學(xué)生說、能讓學(xué)生做的盡量讓學(xué)生做,全面發(fā)展學(xué)生的各方面能力。再通過作業(yè)和探究性課題使學(xué)生的思維活動(dòng)在時(shí)空上得以延續(xù)。5.布置作業(yè):布置作業(yè)時(shí)刻意安排引入:萬有引力、重力、向心力、三者的聯(lián)系,通過引導(dǎo)學(xué)生對比結(jié)果,從中發(fā)現(xiàn)問題:萬有引力與重力向心力的關(guān)系與區(qū)別,為下節(jié)知識的難點(diǎn)突破作好了鋪墊。
[小結(jié)]師:下面同學(xué)們概括總結(jié)本節(jié)所學(xué)的內(nèi)容。請一個(gè)同學(xué)到黑板上總結(jié),其他同學(xué)在筆記本上總結(jié),然后請同學(xué)評價(jià)黑板上的小結(jié)內(nèi)容。 (學(xué)生認(rèn)真總結(jié)概括本節(jié)內(nèi)容,并把自己這節(jié)課的體會寫下來、比較黑板上的小結(jié)和自己的小結(jié),看誰的更好,好在什么地方。) 生:本節(jié)課我們通過伽利略理想斜面實(shí)驗(yàn),分析得出了能量以及動(dòng)能和勢能的概念,從能量的相互轉(zhuǎn)化角度認(rèn)識到,在動(dòng)能和勢能的相互轉(zhuǎn)化過程中,能的總量保持不變,即能量是守恒的。通過這節(jié)課的學(xué)習(xí),使我們建立起了守恒的思想。 點(diǎn)評:總結(jié)課堂內(nèi)容,培養(yǎng)學(xué)生概括總結(jié)能力。 教師要放開,讓學(xué)生自己總結(jié)所學(xué)內(nèi)容,允許內(nèi)容的順序不同,從而構(gòu)建他們自己的知識框架。[布置作業(yè)]課后討論 P3“問題與練習(xí)”中的問題。[課外訓(xùn)練]以豎直上拋的小球?yàn)槔f明小球的勢能和動(dòng)能的轉(zhuǎn)化情況。在這個(gè)例子中是否存在著能的總量保持不變?
2、計(jì)算天體的質(zhì)量首先觀看多媒體展示天體的運(yùn)動(dòng),同時(shí)解釋什么是環(huán)繞天體?什么是中心天體?接著展示相關(guān)問題:①應(yīng)用萬有引力定律求解天體質(zhì)量的基本思路是什么?②求解天體質(zhì)量的方程依據(jù)是什么?教師點(diǎn)撥,學(xué)生分組,合作探究,學(xué)生代表發(fā)言設(shè)計(jì)說明通過創(chuàng)設(shè)問題情境,進(jìn)行由淺至深,由易到難的問題式教學(xué),以激發(fā)學(xué)生的積極思維活動(dòng);通過探究讓學(xué)生建立物理模型,分組討論,求解中心天體質(zhì)量的三種表達(dá)式。在進(jìn)行已有知識的遷移時(shí)重點(diǎn)重復(fù)環(huán)繞和被繞的關(guān)系,使學(xué)生準(zhǔn)確抓住模型中的各個(gè)星體所擔(dān)任的角色。通過小組合作學(xué)習(xí),運(yùn)用類比歸納法得出正確結(jié)論,掌握求解中心天體質(zhì)量的基本思路,以達(dá)到突出教學(xué)重點(diǎn)的目的。3、發(fā)現(xiàn)未知天體通過2個(gè)視頻進(jìn)行了解設(shè)計(jì)說明這部分通過視頻主要激發(fā)學(xué)生相信科學(xué),學(xué)習(xí)科學(xué),讓學(xué)生感知人類探索宇宙的夢想,激發(fā)學(xué)生探索科學(xué)奧秘的熱情,培養(yǎng)熱愛科學(xué)的情感,促使學(xué)生樹立獻(xiàn)身科學(xué)的人生價(jià)值觀。
① 實(shí)驗(yàn)設(shè)計(jì)將學(xué)生分組,利用桌上的器材進(jìn)行探究(幻燈片展示)這個(gè)實(shí)驗(yàn)難度較大,為了降低難度,為實(shí)驗(yàn)探究鋪下第二臺階,要求學(xué)生先分小組討論以下問題(幻燈片展示)有些學(xué)生可能不知如何下手,我會要求學(xué)生先閱讀課本中的實(shí)驗(yàn)描述從中得到一點(diǎn)提示,再讓一兩個(gè)小組同學(xué)回答,這樣既體現(xiàn)了學(xué)生學(xué)習(xí)的主體性又可提高學(xué)生自主思考和語言表達(dá)能力,之后我再進(jìn)行補(bǔ)充完善(幻燈片展示答案),并用幻燈片把實(shí)驗(yàn)步驟展示出來,在學(xué)生實(shí)驗(yàn)過程一直保留,使學(xué)生能朝正確的方向進(jìn)行猜想和操作,為實(shí)驗(yàn)探究鋪下第三個(gè)臺階。② 實(shí)施探究在學(xué)生分組進(jìn)行探究過程,教師巡視解惑,隨時(shí)觀察學(xué)生情況,解答學(xué)生提出的問題,還可用自言自語方式提示應(yīng)注意的一些問題,如儀器的正確使用,操作的規(guī)范等,幫助學(xué)生盡量在規(guī)定時(shí)間內(nèi)順利完成實(shí)驗(yàn)。
問:為什么會出現(xiàn)這樣的情況,男女生之間的拉力存在著怎樣的大小關(guān)系?進(jìn)一步求證這兩個(gè)力的大小關(guān)系經(jīng)過共同討論,得方案:把兩個(gè)彈簧秤勾在一起,重現(xiàn)拔河比賽,分三種情況進(jìn)行。(通過攝像頭把彈簧秤的讀數(shù)放大)兩彈簧稱勾在一起拉,處于靜止不動(dòng)時(shí)(即拔河比賽,雙方處于僵持狀態(tài))兩彈簧稱勾在一起拉,并向一方運(yùn)動(dòng)(即比賽繩子被拉向一方時(shí)的狀態(tài))3、兩彈簧稱勾在一起拉,一方方向慢慢改變(兩力方向始終在一條直線上)實(shí)驗(yàn)結(jié)論:兩彈簧稱的讀數(shù)的變化總是相同的,大小相等,方向相反。得到牛頓第三定律:追問:既然兩個(gè)力大小相等,那么拔河比賽為什么還存在勝負(fù)之分?講清作用力與反作用力作用的受力物體不同,并和學(xué)生討論如何做才會獲勝?;貞?yīng)課前問題:“以卵擊石”為什么雞蛋碎?
進(jìn)一步引導(dǎo)學(xué)生思考利用數(shù)學(xué)知識可寫成等式F=kma學(xué)生很自然就會思考比列系數(shù)K應(yīng)該是多少?通過教師引導(dǎo)學(xué)生舉例各國長度單位不同(如英國:英里、碼、英尺、英寸;中國:市里、市丈、市尺、市寸、市分 )導(dǎo)致交流不便。為了適應(yīng)各國交流需要國際計(jì)量局規(guī)定了一套統(tǒng)一的單位,稱為國際單位制 。取不同的單位制K是不同的,為了簡潔方便,在選取了質(zhì)量和加速度的國際單位(Kg, m/s2)時(shí)規(guī)定K=1。那么就有;F=ma為了紀(jì)念牛頓,就把能使1kg物體獲得1m/s2加速度的力稱做一牛頓,用符號N表示問題:實(shí)際物體受力往往不止一個(gè),多個(gè)力情況應(yīng)該怎么辦呢?平行四邊形法則進(jìn)一步引導(dǎo)學(xué)生得出牛頓第二定律更一般的表達(dá)式: F合=ma思考.討論我們用力提一個(gè)很重的箱子,卻提不動(dòng)它。這個(gè)力產(chǎn)生了加速度嗎?要是產(chǎn)生了,箱子的運(yùn)動(dòng)狀態(tài)卻并沒有改變。為什么?
設(shè)疑自探:一個(gè)壓縮或拉伸的彈簧就是一個(gè)“儲能器”,怎樣衡量形變彈簧蘊(yùn)含能量的多少呢?彈簧的彈性勢能的表達(dá)式可能與那幾個(gè)物理量有關(guān)?類比:物體的重力勢能與物體所受的重力和高度有關(guān)。那么彈簧的彈性勢能可能與所受彈力的大小和在彈力方向上的位置變化有關(guān),而由F=kl知彈簧所受彈力等于彈簧的勁度系數(shù)與形變量的乘積。預(yù)測:彈簧的彈性勢能與彈簧的勁度系數(shù)和形變量有關(guān)。學(xué)生討論如何設(shè)計(jì)實(shí)驗(yàn): ①、用同一根彈簧在幾次被壓縮量不同時(shí)釋放(勁度系數(shù)相同,改變形變量),觀察小車被彈開的情況。②、分別用兩根彈簧在被壓縮量相同時(shí)釋放(形變量相同,勁度系數(shù)不同),觀察小車被彈開的情況。交流探究結(jié)果:彈性勢能隨彈簧形變量增大而增大。隨彈簧的勁度系數(shù)的增大而增大。
一、說教材《質(zhì)點(diǎn) 參考系和坐標(biāo)系》是人教版普通高中物理必修一第一章第一課的內(nèi)容。本節(jié)課主要介紹了質(zhì)點(diǎn)、參考系、坐標(biāo)系的基本概念。通過本節(jié)課的學(xué)習(xí)為進(jìn)一步學(xué)習(xí)后續(xù)課程起到了鋪墊的作用。根據(jù)上述教材的結(jié)構(gòu)和內(nèi)容分析,又考慮到高一年級學(xué)生的認(rèn)知結(jié)構(gòu)及其心理特征,我制定了以下三維教學(xué)目標(biāo):1、知識與技能:知道質(zhì)點(diǎn)的概念及條件;知道參考系的概念及作用;掌握坐標(biāo)系的簡單應(yīng)用。2、過程與方法:促進(jìn)學(xué)生自主學(xué)習(xí),讓學(xué)生積極參與、樂于探究、勇于實(shí)驗(yàn)、勤于思考,培養(yǎng)學(xué)生的科學(xué)探究能力。3、情感態(tài)度與價(jià)值觀:通過質(zhì)點(diǎn) 參考系和坐標(biāo)系的學(xué)習(xí),使學(xué)生了解生活與物理的關(guān)系,讓學(xué)生學(xué)會用科學(xué)的思維去看待事物。根據(jù)普通高中物理課程標(biāo)準(zhǔn),并在吃透教材的基礎(chǔ)上,我確定了以下教學(xué)重點(diǎn)和難點(diǎn):教學(xué)重點(diǎn):質(zhì)點(diǎn)概念的建立。只有掌握了這一點(diǎn)才能更加準(zhǔn)確的理解和掌握后續(xù)教材的相關(guān)內(nèi)容。