4、學(xué)習(xí)全詞:(1)背景介紹,讓學(xué)生看課文中的年代,然后讓學(xué)生回憶1925年的毛澤東的情況,老師適當(dāng)提示,讓學(xué)生了解其背景。(出示幻燈片)(2)學(xué)生自由朗讀,結(jié)合注釋和背景理解詩(shī)詞。(3)師生共同理解全詞①先讓學(xué)生齊讀前三句,思考正確的語(yǔ)序,并用正常的語(yǔ)序解釋。②品味第三到第十句,這里是教學(xué)的一個(gè)重點(diǎn),要讓學(xué)生先讀,再理解,在此基礎(chǔ)上訓(xùn)練學(xué)生的想象能力。③分析上闕中的最后三句。④小結(jié)上闕。提出了一個(gè)問(wèn)題“誰(shuí)主沉浮”讓學(xué)生在文中找內(nèi)容回答,然后轉(zhuǎn)入下闕內(nèi)容的分析。⑤分析下闕內(nèi)容,回答“誰(shuí)主沉浮”的問(wèn)題,突出本文主旨5、描繪詩(shī)詞形象:學(xué)生用自己的語(yǔ)言把上闕的內(nèi)容生動(dòng)地描繪出來(lái)。6、欣賞學(xué)生優(yōu)秀作品。(根據(jù)時(shí)間具體而定,也可以作為課后作業(yè))
四、教學(xué)方法和學(xué)法。課前學(xué)生搜集有關(guān)《詩(shī)經(jīng)》的資料必不可少。另外,時(shí)隔數(shù)千年,年代久遠(yuǎn),文字的障礙很大,然而,過(guò)分糾纏于文字的疏通會(huì)破壞詩(shī)歌的“氣”,喪失詩(shī)歌的“神”,所以在學(xué)習(xí)時(shí),應(yīng)舍去條分縷析的理論評(píng)價(jià),指導(dǎo)學(xué)生結(jié)合注釋疏通文字,然后引領(lǐng)他們經(jīng)由文字再現(xiàn)形象和事件,經(jīng)由形象和事件領(lǐng)略情感,感受其中濃濃的詩(shī)情。誦讀的環(huán)節(jié)是重要的,配以二胡獨(dú)奏《長(zhǎng)相思》,營(yíng)造意境,學(xué)生沉浸在音樂(lè)營(yíng)造的意境中反復(fù)吟詠,讀出節(jié)奏,讀出音調(diào),讀出感情,細(xì)細(xì)體味,讓或優(yōu)或喜的情愫縈繞心間,我們就觸到了先民的靈魂。比興手法為《詩(shī)經(jīng)》獨(dú)創(chuàng),重章疊句同樣別致而新鮮,教學(xué)過(guò)程中結(jié)合具體語(yǔ)境讓學(xué)生自己去發(fā)現(xiàn)并進(jìn)行討論,不搞枯燥的知識(shí)傳授。還引入講故事、改寫(xiě)兩種活潑的學(xué)習(xí)形式,從而達(dá)到加深理解的目的。
3、拓展延伸,啟迪心智,創(chuàng)設(shè)課堂訓(xùn)練營(yíng)。三、說(shuō)學(xué)法1、紙上得來(lái)終覺(jué)淺,圈點(diǎn)、勾畫(huà)、批注法,學(xué)好文言基本功。2、自主合作加探究,眼耳口腦手并用,破疑解難在其中。四、說(shuō)課時(shí)安排《鴻門(mén)宴》篇幅較長(zhǎng),文言知識(shí)較豐富,文章內(nèi)涵豐厚,因此我設(shè)計(jì)用五課時(shí)教學(xué)本文。第一課時(shí):了解作家作品,積累文言知識(shí),感受作者隱忍發(fā)憤的著書(shū)精神(初讀)第二課時(shí):理清故事情節(jié),概括人物形象,學(xué)習(xí)客觀地評(píng)論歷史人物,(熟讀)第三課時(shí):進(jìn)一步梳理文言知識(shí),精讀課文,要求讀透。(精讀)第四課時(shí):通過(guò)對(duì)人物、事件的賞析,加深學(xué)生對(duì)人物的理解,鍛煉學(xué)生的開(kāi)放性思維,由學(xué)生自主認(rèn)識(shí)到人物的性格,悲劇的原因等問(wèn)題。(賞讀)第五課時(shí):補(bǔ)充課本教學(xué)內(nèi)容:同學(xué)生一起閱讀古今關(guān)于劉邦項(xiàng)羽的一些篇章:讓學(xué)生投入進(jìn)來(lái),把握自己眼中的項(xiàng)羽。(展讀)在文言文學(xué)習(xí)的過(guò)程中,采取五步學(xué)習(xí)法:初讀-熟讀-精讀-賞讀-展讀(板書(shū))
一.教材理解教材地位與作用:本單元“閱讀與鑒賞”部分,本單元要求學(xué)生能在了解詩(shī)歌創(chuàng)作的時(shí)代背景的情況下通過(guò)反復(fù)誦讀詩(shī)歌,把握其中豐富的意象,領(lǐng)悟詩(shī)歌獨(dú)特的意境和詩(shī)人所要表達(dá)的情感?!队晗铩肥乾F(xiàn)代派大師戴望舒的成名作和前期的代表作,他曾因此而贏得了“雨巷詩(shī)人”的雅號(hào)。本單元以《雨巷》為例子給學(xué)生展示了象征主義詩(shī)歌的特點(diǎn),《雨巷》運(yùn)用了象征性的抒情手法。詩(shī)中那狹窄陰沉的雨巷,在雨巷中徘徊的獨(dú)行者,以及那個(gè)像丁香一樣結(jié)著愁怨的姑娘,都是象征性的意象。這些意象又共同構(gòu)成了一種象征性的意境,含蓄地暗示出作者即迷惘感傷又有期待的情懷,并給人一種朦朧而又幽深的美感。富于音樂(lè)性是《雨巷》的另一個(gè)突出的藝術(shù)特色。詩(shī)中運(yùn)用了復(fù)沓、疊句、重唱等手法,造成了回環(huán)往復(fù)的旋律和宛轉(zhuǎn)悅耳的樂(lè)感。因此我把本課的教學(xué)重點(diǎn)和難點(diǎn)確定為:教學(xué)重點(diǎn):通過(guò)反復(fù)誦讀,領(lǐng)略詩(shī)歌的音樂(lè)美以及分析其成因教學(xué)難點(diǎn):分析意象以及其象征意義初步掌握鑒賞詩(shī)歌的方法
【教學(xué)目標(biāo)】我設(shè)置的本課的教學(xué)目標(biāo)有三個(gè):1、知識(shí)與技能(1)了解曹雪芹及《紅樓夢(mèng)》(2)學(xué)習(xí)通過(guò)一個(gè)人物的行蹤、所見(jiàn)所聞,介紹典型環(huán)境,認(rèn)識(shí)封建貴族階級(jí)豪奢極恥的生活以及森嚴(yán)的等級(jí)、禮儀制度(3)分析小說(shuō)人物出場(chǎng)的描寫(xiě)藝術(shù),培養(yǎng)學(xué)生分析小說(shuō)人物形象的能力。(4)一葉落而知秋”,通過(guò)對(duì)“林黛玉進(jìn)賈府”這一故事情節(jié)的把握是否能引發(fā)對(duì)《紅樓夢(mèng)》的認(rèn)知興趣,并找到一個(gè)突破口,有針對(duì)性地進(jìn)行自主探究,進(jìn)而進(jìn)行個(gè)性化解讀。(5)整體認(rèn)知小說(shuō),認(rèn)識(shí)小說(shuō)悲劇的必然性和思想價(jià)值.2、過(guò)程與方法(1)用直觀演示和歸納探究法分析文章要點(diǎn)。(2)用討論探究法體驗(yàn)作者對(duì)文中人物的情感態(tài)度。3、情感態(tài)度價(jià)值觀(1)正確理解《紅樓夢(mèng)》的思想內(nèi)涵,培養(yǎng)學(xué)生熱愛(ài)祖國(guó)傳統(tǒng)文化的思想感情。(2)認(rèn)識(shí)封建大家族的腐朽沒(méi)落,理解賈寶玉追求個(gè)性自由反封建的精神。
生2:頷聯(lián)的意思是只聽(tīng)到禁衛(wèi)軍中傳來(lái)夜間巡邏的梆子聲,不再向?qū)m中那樣安逸地聽(tīng)到有雞人打鳴報(bào)時(shí)的聲音了。生3:頸聯(lián)的意思是說(shuō)事變發(fā)生那天軍隊(duì)發(fā)生嘩變停留不前,但當(dāng)年唐玄宗以為自己可以和貴妃天天在一起,對(duì)天上的牽牛和織女一年一度的會(huì)見(jiàn)還加以嘲笑呢。生4:尾聯(lián)的含義是為什么唐玄宗當(dāng)了四十五年的皇帝,還不如普通百姓夫妻恩愛(ài),長(zhǎng)相廝守。師:好的。請(qǐng)大家再齊讀一遍詩(shī)文,做到人人都能疏通詩(shī)的含義。學(xué)生再次齊讀。第三環(huán)節(jié):專(zhuān)項(xiàng)探究師:白居易曾說(shuō):“文章合為時(shí)而著,歌詩(shī)合為事而作。”這首詩(shī)就是作者途經(jīng)馬嵬驛,詠馬嵬之變這一歷史事件而作,所以我們鑒賞的第三步,就是通過(guò)標(biāo)題和詩(shī)文,弄清詩(shī)中的歷史事件。請(qǐng)同學(xué)們找出詩(shī)中哪些詩(shī)句描述了這一事件?
說(shuō)教材A.教材簡(jiǎn)析《琵琶行(并序)》是人教版《普通高中課程標(biāo)準(zhǔn)實(shí)驗(yàn)教科書(shū)語(yǔ)文》必修3第二單元的一篇講讀課文。本單元學(xué)習(xí)的是唐代詩(shī)歌,共七首詩(shī)?!杜眯校ú⑿颍肥翘拼F(xiàn)實(shí)主義詩(shī)人白居易寫(xiě)的一首歌行體長(zhǎng)篇敘事詩(shī),是我國(guó)古代敘事詩(shī)和音樂(lè)詩(shī)中的“千古絕喝”。詩(shī)歌主題鮮明、人物形象生動(dòng),抒情真切細(xì)膩,具有深刻的思想內(nèi)容和卓越的藝術(shù)技巧。B.教學(xué)目標(biāo)《全日制普通高中高級(jí)中學(xué)語(yǔ)文教學(xué)大綱》明確要求我們:在閱讀教學(xué)過(guò)程中要引導(dǎo)學(xué)生“感受文學(xué)形象,品味文學(xué)作品的語(yǔ)言和藝術(shù)技巧,初步鑒賞文學(xué)作品”。而本單元的教學(xué)要求是培養(yǎng)學(xué)生詩(shī)歌鑒賞的能力。根據(jù)教學(xué)大綱和單元教學(xué)要求,結(jié)合本課特點(diǎn),我制定本課的教學(xué)目標(biāo)是:1.知識(shí)目標(biāo):了解文學(xué)常識(shí);積累重點(diǎn)文言實(shí)詞;品味主旨句“同是天涯淪落人,相逢何必曾相識(shí)”的內(nèi)涵;感知作者把音樂(lè)描寫(xiě)與聽(tīng)者、演奏者的感情融為一體的寫(xiě)作特點(diǎn)。
一. 教材分析1. 本單元的中心話題是“計(jì)算機(jī)(Computers)”,內(nèi)容涉及計(jì)算機(jī)的發(fā)展歷史,計(jì)算機(jī)的應(yīng)用等。本節(jié)課是該單元的第一課時(shí),我將Warming up, Pre-reading and Comprehending這四部分整合為一節(jié)精讀課。其中。Reading部分是題為WHO AM I?的文章,以第一人稱(chēng)的擬人手法介紹了計(jì)算機(jī)發(fā)長(zhǎng)演變的歷史和計(jì)算機(jī)在各個(gè)領(lǐng)域的應(yīng)用,其主旨是表達(dá)計(jì)算機(jī)的發(fā)展變化之快以及在生活中用途之廣。而Warming up部分以圖片的形式展現(xiàn)了計(jì)算機(jī)的發(fā)展歷程;Pre-reading中的問(wèn)題和排序分別是為了預(yù)測(cè)語(yǔ)篇的內(nèi)容和測(cè)試學(xué)生對(duì)計(jì)算機(jī)歷史了解的情況;Comprehending則通過(guò)各項(xiàng)練習(xí)訓(xùn)練學(xué)生的閱讀技能,從而加深對(duì)文章的理解。可見(jiàn)這幾部分是一個(gè)有機(jī)的整體。2. 教學(xué)目標(biāo):1) 語(yǔ)言目標(biāo):重點(diǎn)詞匯及短語(yǔ):abacus, calculate, calculator, PC, laptop, PDA, robot, analytical, technological, universal, mathematical, artificial, intelligent, network, explore, in common, as a result.重點(diǎn)句子:a. My real father was Alan Turing, who in 1963 wrote a book to describe how computers could be made to work, and build a “universal machine” to solve any mathematical problem.
When it comes to the students’ studying methods, I'd like to introduce my Ss first. The Ss have a good command of basic language points. They’re interested in learning English, and they take an active part in English class, so they will have fun in autonomous, cooperative and inquiry learning. I will just serve as a guide, showing them the way to explore how to make more progress in their English learning.Now it’s time for the most important stage of this lesson. My teaching procedures are arranged as follows:Step1.Leading-in (3 minute)Play a video of a wide variety of wildlife to introduce my topic. Step2. Speaking (12 minutes)We will use our textbook Page25. Let the Ss fast read the short paragraph to warm up. Ask them to talk about the report on some endangered wildlife in China with the dialogue patterns on the screen. Lastly, I will invite some groups to demonstrate their dialogues about saving wildlife in China.Step3.English play (3 minutes)Watch another video in praise of their excellent performance just now. It’s about Jack Chen’s(成龍)and Yang Ziqiong’s wildlife protection.Step4. Listening (twice 13 minutes)This time, I’ll ask the Ss to fill in the blanks of the monologue of the 2 movie stars above. Step5.Discussion (3 minutes)Which would you like to choose to wear, clothes made of cotton, artificial leather or animal skins? Why ?Step6. Summary (3 minutes)1. If there were no wildlife, there wouldn’t exist human beings. If the buying stops, the killing can, too.2. Animals are our friends. To love animals is to love ourselves. Stop hunting, killing and destroying wildlife.3. Let’s live in harmony with all the living things in the world. Step7. Music appreciation (3 minutes)Let the Ss appreciate the song Earth Song by Michael Jackson. Last but not the least, I will show you my blackboard design.
Then I would ask them to think of a funny English or Chinese and tell it to partners. While telling stories, they can use expressions and some acting to help make the story funny. 5 minutes would be given to do this.Those stories they told there will be the material for their writing. Soletting them tell it at first is helpful. And they can make a difference between telling a funny story and writing it down. Generally speaking, it is difficult forstudents to write well because they don’t know what to write and how to write. Asking them to tell their own stories at first can help them come up with what to write.After their telling, I would invite someone to share his/her story with all of us and I would write it down on the blackboard.This example story would be used as a sample to illustrate the format of funny story. Different from a story from teacher or textbook, a story from students can obviously become a interesting material to draw students’ attention.Then I would ask the whole class to put this story into several parts. It might be a little bit difficult for them. So I would ask them to find out whether all the sentences are necessary. After delete some sentences, there are 6 sentences left behind. Then they can easily put them into three parts. After interaction with students, I would teach them the right terms for each part and conclude the format of funny story.This step is the key and difficult point in my lesson. So I mainly usetask-based teaching method in this part and the task for students was divided into several stages. With the separated difficult level, students can find there are usually three parts in writing. They can also learn to write without the unnecessary parts in the process of analyzing. And then I wouldn’t rush to tell them the right terms to them directly. Instead, I would ask them to name them by their own. A confused mind is better for acquiring knowledge.While-writing:Then I would give students 7 minutes to write down this story, without other requirements.With all the preparations in pre-writing, students’ difficulties were cleared. So it would be much easier for them to write down the story within 7 minutes. There are no other requirements because students’ first writing is actually a drafting. It would be revise and edit several times later. Writing, as a skill
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.
學(xué)法指導(dǎo):高一學(xué)生對(duì)文言文閱讀已具備了一些基礎(chǔ)知識(shí)和積累,但對(duì)如何學(xué)習(xí)文言文,還是一個(gè)新課題,因此教師應(yīng)引導(dǎo)學(xué)生掌握學(xué)習(xí)方法,運(yùn)用已有的知識(shí)框架同化新信息,建立新的智能,逐步走向獨(dú)立學(xué)習(xí)的境界。一、引導(dǎo)學(xué)生利用課文注釋?zhuān)褂霉ぞ邥?shū)自己翻譯,必要時(shí)教師進(jìn)行點(diǎn)撥、解難,培養(yǎng)自學(xué)能力。二、告訴學(xué)生翻譯文言文要遵循的原則。三、調(diào)動(dòng)學(xué)生思考、討論、交流的積極性,教師適時(shí)點(diǎn)撥,培養(yǎng)學(xué)生發(fā)現(xiàn)問(wèn)題、解決問(wèn)題的能力。四、提示學(xué)生反復(fù)誦讀課文,體會(huì)文章所闡述的道理。五、鼓勵(lì)學(xué)生及時(shí)歸納學(xué)習(xí)文言文的方法,注意積累文言文知識(shí)。教學(xué)程序:教學(xué)本課可安排2課時(shí)。第一課時(shí):1、導(dǎo)入新課:首先給學(xué)生介紹毛澤東的七絕詩(shī)《為李進(jìn)同志題所攝廬山仙人洞照》:“暮色蒼??磩潘?,亂云飛渡仍從容。天生一個(gè)仙人洞,無(wú)限風(fēng)光在險(xiǎn)峰。”學(xué)生通過(guò)誦讀領(lǐng)會(huì)了“無(wú)限風(fēng)光在險(xiǎn)峰”一句的含義。隨后因勢(shì)利導(dǎo),引出課題,指出今天我們要學(xué)習(xí)的王安石的《游褒禪山記》,就含有類(lèi)似的深邃哲理。
【教學(xué)目標(biāo)】知識(shí)與技能:了解我國(guó)不同等級(jí)城市的劃分,并理論聯(lián)系實(shí)際辨別現(xiàn)實(shí)社會(huì)的城市等級(jí)運(yùn)用有關(guān)原理,說(shuō)明不同等級(jí)城市服務(wù)范圍的差異。了解城市服務(wù)范圍與地理位置的關(guān)系。掌握不同等級(jí)城市的分布特點(diǎn)了解稱(chēng)城市六邊形理論,并能用其解釋荷蘭圩田居民點(diǎn)設(shè)置問(wèn)題過(guò)程與方法:通過(guò)對(duì)棗強(qiáng)鎮(zhèn)及上海城市等級(jí)演化分布的學(xué)習(xí),掌握不同等級(jí)城市城市服務(wù)范圍與功能以及城市等級(jí)提高的基本條件通過(guò)對(duì)德國(guó)城市分布案例的學(xué)習(xí),總結(jié)歸納出不同等級(jí)城市分布規(guī)律通過(guò)城市六邊形理論的學(xué)習(xí),學(xué)會(huì)分析城市居民點(diǎn)布局等現(xiàn)實(shí)問(wèn)題情感態(tài)度與價(jià)值觀:通過(guò)學(xué)生對(duì)我國(guó)不同等級(jí)城市(經(jīng)濟(jì)、人口、交通、服務(wù)種類(lèi))等相關(guān)資料的搜集,讓學(xué)生關(guān)心我國(guó)基本地理國(guó)情,增強(qiáng)熱愛(ài)祖國(guó)的情感。養(yǎng)成求真、求實(shí)的科學(xué)態(tài)度,提高地理審美情趣。
1.導(dǎo)入新課:通過(guò)問(wèn)卷調(diào)查“如果你是一名普通的工薪階層人士,要置業(yè)(買(mǎi)房),以下因素中,哪三個(gè)你認(rèn)為是最重要的?”引出交通運(yùn)輸?shù)闹匾?,引入課題交通運(yùn)輸方式和布局的變化對(duì)聚落空間形態(tài)和商業(yè)網(wǎng)點(diǎn)布局的影響。2.新課講授:要了解通運(yùn)輸方式和布局的變化對(duì)聚落空間形態(tài)的影響,就先跟學(xué)生們一起復(fù)習(xí)有關(guān)聚落的基本知識(shí)和聚落的形式和空間形態(tài)的知識(shí)。再通過(guò)讀圖分析比較交通條件對(duì)聚落空間形態(tài)影響,通過(guò)補(bǔ)充知識(shí)《大運(yùn)河沿岸城市的興衰》來(lái)分析說(shuō)明交通線的發(fā)展會(huì)帶動(dòng)聚落空間形態(tài)的變化。對(duì)第二部分“對(duì)商業(yè)網(wǎng)點(diǎn)分布的影響”也是通過(guò)上面的順序即先對(duì)商業(yè)網(wǎng)點(diǎn)相關(guān)知識(shí)作一下簡(jiǎn)要的提問(wèn),再通過(guò)具體案例分析交通條件對(duì)對(duì)商業(yè)網(wǎng)點(diǎn)密度,對(duì)商業(yè)網(wǎng)點(diǎn)位置,對(duì)集鎮(zhèn)發(fā)展的影響??偟膩?lái)說(shuō),這節(jié)課的教學(xué),主要依靠具體的案例加深學(xué)生對(duì)知識(shí)的理解與掌握。
2.比較物體的高度和影長(zhǎng)時(shí),要在同一( )、同一( )進(jìn)行。3.在同一時(shí)間、同一地點(diǎn),物體的高度和影長(zhǎng)成( )比例。4.同樣高度的物體在不同時(shí)間、不同地點(diǎn)測(cè)出的影長(zhǎng)是會(huì)( )的。 5、李明在操場(chǎng)上插上幾根長(zhǎng)短不同的的竹竿,在同一時(shí)間里測(cè)量這幾根竹竿的長(zhǎng)和相應(yīng)的影長(zhǎng)情況如下表: 竹竿長(zhǎng)/米11.21.8245影長(zhǎng)/米0.50.60.9122.5比值 (1)算出竹竿和影長(zhǎng)的比值,并填在表格中。 (2)通過(guò)測(cè)量和計(jì)算,你發(fā)現(xiàn)了什么? (3)這時(shí)李明測(cè)出旗桿的影長(zhǎng)是5米,你能求出旗桿的實(shí)際高度是多少米? (4)這時(shí)王剛測(cè)出一棵松樹(shù)的影長(zhǎng)是2.4米,你能算出這棵松樹(shù)的實(shí)際高度嗎? 6、為了測(cè)量出學(xué)校旗桿的高度,同學(xué)們找來(lái)了一根長(zhǎng)8分米的木棍立在旗桿旁,發(fā)現(xiàn)木棍的影長(zhǎng)是6分米,同時(shí)又發(fā)現(xiàn)旗桿的影長(zhǎng)是7.5米,你能求出旗桿的高度嗎? 7.在同一時(shí)刻,小璐測(cè)得她的影長(zhǎng)為1米,距她不遠(yuǎn)處的一棵槐樹(shù)的影長(zhǎng)為5米。已知小璐的身高為1.3米,這棵槐樹(shù)的有多高。
基于以上分析,為使本堂課圍繞重點(diǎn)、突破難點(diǎn),同時(shí)讓學(xué)生在課堂教學(xué)中能力得到提高,我設(shè)計(jì)如下教學(xué)過(guò)程。(一)創(chuàng)設(shè)情景認(rèn)識(shí)形變由同學(xué)們已有的形變知識(shí)入手,引入新課。教師演示:①?gòu)椈傻膲嚎s形變;②彈簧的拉伸形變③視頻播放:竹竿形變、鋼絲的扭轉(zhuǎn)形變。得出形變的概念及各類(lèi)形變。[設(shè)計(jì)意圖:我從生活情景中引入新課,是為了激發(fā)學(xué)生的好奇心,為學(xué)生學(xué)習(xí)重點(diǎn)和難點(diǎn)內(nèi)容作鋪墊。]設(shè)問(wèn):摩天大樓在風(fēng)的吹拂下會(huì)不會(huì)擺動(dòng),發(fā)生形變嗎?演示微小形變放大實(shí)驗(yàn):由于這種形變不容易觀察,會(huì)使學(xué)生產(chǎn)生疑問(wèn):到底有沒(méi)有發(fā)生形變?解決的辦法是微小形變的演示實(shí)驗(yàn)。為什么光點(diǎn)會(huì)往下移?讓學(xué)生帶著問(wèn)題思考后得出結(jié)論:是由于桌面發(fā)生了形變,但是形變不明顯。為后面解決壓力和支持力都是彈力做好鋪墊。[設(shè)計(jì)意圖:使學(xué)生知道“放大”是一種科學(xué)探究的方法。]
通過(guò)這個(gè)示例呢,我們可以得到解決向心力問(wèn)題的一般的步驟,確定對(duì)象,找出軌跡,找出圓心,然后進(jìn)行受力分析,讓同學(xué)們參考這樣的步驟,逐步的解決圓周運(yùn)動(dòng)的問(wèn)題,對(duì)于變速圓周運(yùn)動(dòng),我通過(guò)鏈球運(yùn)動(dòng)進(jìn)行引入,這里是一個(gè)鏈球運(yùn)動(dòng)的視頻,在同學(xué)們觀看視頻之前,我給同學(xué)們提出問(wèn)題,鏈球收到繩子的拉力,做的是勻速圓周運(yùn)動(dòng)嗎? 然后再課堂上我們?cè)僮鲆粋€(gè)小實(shí)驗(yàn), 我們可以通過(guò)改變拉線的方式來(lái)調(diào)節(jié)小球的速度大小嗎? 那么對(duì)小球,做加速圓周運(yùn)動(dòng),進(jìn)行受力分析,我們可以看到,小球做加速運(yùn)動(dòng)時(shí),他所受到的力,并不是嚴(yán)格通過(guò)軌跡的圓心,在進(jìn)行分析的時(shí)候,特別強(qiáng)調(diào),小桶所受力的切線方向分力,和法線方向分力,切線方向分力,改變小球運(yùn)動(dòng)速度大小,法線方向分力,改變了小球運(yùn)動(dòng)的方向,法線方向的分力,在這里就是向心力,產(chǎn)生了向心加速度,通過(guò)這樣一個(gè)例子進(jìn)行分析,同學(xué)們是比較容易理解的,
(一)地位《生活中的圓周運(yùn)動(dòng)》這節(jié)課是新課標(biāo)人教版《物理》必修第二冊(cè)第5章《曲線運(yùn)動(dòng)》一章中的第7節(jié),也是該章最后一節(jié)。本節(jié)課是在學(xué)生學(xué)習(xí)了圓周運(yùn)動(dòng)、向心加速度、向心力以后的一節(jié)應(yīng)用課,通過(guò)研究圓周運(yùn)動(dòng)規(guī)律在生活中的具體應(yīng)用,使學(xué)生深入理解圓周運(yùn)動(dòng)規(guī)律,并且結(jié)合日常生活中的某些生活體驗(yàn),加深物理知識(shí)在頭腦中的印象。(二)教材處理教材中的“火車(chē)轉(zhuǎn)彎”與“汽車(chē)過(guò)拱橋”根據(jù)學(xué)生接受的難易程度,順序作了對(duì)調(diào),并把最后一部分“離心運(yùn)動(dòng)”放到下一節(jié)課處理。(三)教學(xué)目標(biāo)1.知識(shí)與技能目標(biāo)(1)進(jìn)一步加深對(duì)向心力的認(rèn)識(shí),會(huì)在實(shí)際問(wèn)題中分析向心力的來(lái)源。(2)培養(yǎng)學(xué)生獨(dú)立觀察、分析問(wèn)題、解決問(wèn)題的能力,提高學(xué)生概括總結(jié)知識(shí)的能力。(3)了解航天器中的失重現(xiàn)象。2.過(guò)程與方法目標(biāo)(1)學(xué)會(huì)分析圓周運(yùn)動(dòng)方法,會(huì)分析拱形橋、彎道等實(shí)際的例子,培養(yǎng)理論聯(lián)系實(shí)際的能力。
1、如圖,OA、OB是兩條射線,C是OA上一點(diǎn),D、E是OB上兩點(diǎn),則圖中共有 條錢(qián)段、它們分別是 ;圖中共有 射線,它們分別是 。2、如果線段AB=5cm,BC=3cm,那么A、C兩點(diǎn)間的距離是 3、(1)用度、分、秒表示48.26° (2)用度表示37°28′24″ 4、從3點(diǎn)到5點(diǎn)30分,時(shí)鐘的時(shí)針轉(zhuǎn)過(guò)了 度。5、一輪船航行到B處測(cè)得小島A的方向?yàn)楸逼?0°,則從A處觀測(cè)此B處的方向?yàn)椋? ) A. 南偏東30° B. 東偏北30° C. 南偏東60° D. 東偏北60°6、已知,OA⊥OC,∠AOB∶∠AOC=2∶3,則∠BOC的度數(shù)為( )A. 30° B. 150° C. 30°或150° D. 不同于上述答案7、如圖,AO⊥OB,直線CD過(guò)點(diǎn)O,且∠BOD=130°,求∠AOD的大小。8、已知:如圖,B、C兩點(diǎn)把線段AD分成2∶4∶3三部分,M是AD的中點(diǎn),CD=6,求:線段MC的長(zhǎng)。9、平面上有n個(gè)點(diǎn)(n≥2)且任意三個(gè)點(diǎn)不在同一直線上,經(jīng)過(guò)每?jī)蓚€(gè)點(diǎn)畫(huà)一條直線,一共可以畫(huà)多少條直線?遷移:某足球比賽中有20個(gè)球隊(duì)進(jìn)行單循環(huán)比賽(每?jī)申?duì)之間必須比賽一場(chǎng)),那么一共要進(jìn)行多少場(chǎng)比賽?