外研版小升初英语总复习资料

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周末重难点外研版小学英语小升初总复习
一、字母
能按照四线三格正确书写26个字母的大小写并书读字母。

二.词汇
1.学习用品:
pen钢笔pencil铅笔pencil-case铅笔盒ruler尺子book书bag包newspaper 报纸schoolbag书包eraser橡皮dictionary词典
2.人体(body):
foot脚head头face脸hair头发nose鼻子mouth嘴eye眼睛ear耳朵arm手臂hand手finger手指leg腿
3.【颜色(colours)】:
red红blue蓝yellow黄green绿white白black黑pink粉红purple紫orange 橙brown棕
4.【动物(animals)】:
cat猫dog狗pig猪duck鸭rabbit兔horse马elephant大象ant蚂蚁fish鱼snake蛇mouse老鼠kangaroo袋鼠monkey猴panda熊猫bear熊lion狮子tiger 老虎fox狐狸deer鹿hen母鸡sheep绵羊goat山羊cow奶牛bird 鸟camel 骆驼frog青蛙cock公鸡dragon龙owl 猫头鹰parrot鹦鹉
5.【人物(people)】:
friend朋友boy男孩girl女孩mother母亲father父亲sister姐妹brother 兄弟uncle叔叔舅舅man男人woman女人Mr.先生Miss小姐
lady女士;小姐mom妈妈dad爸爸parents父母grandparents祖父母
grandma/grandmother(外)祖母grandpa/grandfather(外)祖父aunt姑姑cousin堂(表)兄弟;堂(表)姐妹son儿子daughter女儿baby婴儿classmate同学people人物robot机器人
6【职业(jobs)】:
teacher教师student学生doctor医生nurse护士driver司机farmer农民singer歌唱家writer作家actor男演员actress女演员artist画家TV reporter电视台记者policeman(男)警察police警察
7.【食品,饮料(food & drink)】:
rice米饭bread面包beef牛肉milk牛奶water水egg蛋fish鱼tofu豆腐cake蛋糕hot dog热狗hamburger汉堡包biscuit饼干noodles面条meat肉chicken鸡肉vegetable蔬菜soup汤ice冰ice-cream冰淇淋cola可乐juice果汁breakfast早餐lunch午餐dinner/supper晚餐meal一餐cake蛋糕chocolate巧克力sandwich三明治cheese 奶酪sausage香肠dumpling 饺子tea 茶coffee咖啡8.水果,蔬菜(fruit & vegetables):
apple苹果banana香蕉pear梨orange橙watermelon西瓜tomato西红柿potato土豆peach桃strawberry草莓carrot胡萝卜cabbage卷心菜mango芒果
9.【衣服(clothes)】:
jacket夹克衫shirt衬衫T-shirt丅恤衫skirt短裙子dress连衣裙
shoes鞋子sweater毛衣coat上衣raincoat雨衣shorts短裤hat(有沿的)帽子
cap便帽sunglasses太阳镜trousers裤子cloth布
10.【交通工具(vehicles)】:
bike自行车bus公共汽车train火车boat小船ship轮船car小汽车taxi出租车jeep吉普车plane/airplane飞机
11.【事物(other things)】:
thing东西window窗户door门desk课桌chair椅子bed床puter计算机light灯teacher's desk讲台picture图画;照片wall墙壁floor地板ball 球baseball 棒球basket ball篮球table tennis乒乓球clock钟表card 卡片postcard明信片football/soccer足球present礼物lamp 台灯phone电话sofa沙发shelf书架table桌子TV电视photo照片plate盘子knife 刀fork叉chopsticks筷子gift礼物toy玩具doll洋娃娃ball球balloon气球kite风筝jigsaw 拼图游戏box盒子umbrella伞violin小提琴piano钢琴trumpet小号yo-yo溜溜球hole洞toothbrush牙刷menu菜单e-card电子卡片e-mail电子邮件money钱
12.【地点(locations)】:
home家room房间bedroom卧室living room起居室classroom教室school学校park公园library图书馆post office邮局police office警察局hospital医院cinema电影院bookstore书店farm农场zoo动物园garden花园study书房playground操场teacher's office教师办公室library图书馆washroom卫生间art room绘画教室puter room计算机教室music room音乐教室TV room电视机房factory工厂pet shop宠物商店science museum科学博物馆the Great Wall长城supermarket超市bank银行country国家village 乡村city城市hometown家乡bus stop公共汽车
13.【气象(weather)】:
cold寒冷的warm温暖的cool凉爽的snow下雪sunny晴朗的
hot炎热的rain下雨windy有风的cloudy多云的weather report天气预报
14.【Number 数字】
One一two二three三four四five 五six六seven 七eight八nine九ten十eleven十一twelve十二
thirteen十三fourteen十四fifteen十五sixteen十六seventeen十七eighteen十八nineteen 十九
twenty 二十thirty三十forty四十fifty五十sixty六十seventy七十eighty 八十ninety九十hundred百thousand 一千million 百万
15.week【周,星期,时间】
weekday周日weekend周末Sunday星期日Monday 星期一Tuesday星期二Wednesday 星期三Thursday 星期四Friday 星期五Saturday 星期六time 时间hour小时
day 天today今天morning早上afternoon下午evening 晚上night夜间soon 不久
often经常、时常usually通常sometimes有时never从不
16.月份(Mouths):
January 一月February 二月March 三月April 四月May 五月June 六月July 七月August 八月September 九月October 十月November 十一月December 十二月
17.Sport (体育运动):
football 足球basketball 篮球table tennis 乒乓球baseball 棒球ball 球skating 滑冰taiji 太极
High jump 跳高long jump 跳远running 跑步walk 竞走wushu武术swimming 游泳【季节(seasons)】:
spring 春summer 夏autumn 秋winter 冬
18.国家——国籍(countries)】:
China---Chinese 中国————中国人(的);汉语
America----American 美国——美国人(的)England—English 英语---英语(的)Australia——Australian 澳大利亚——澳大利亚人(的)
Canada---Canadian 加拿大----加拿大人(的)Japan---Japanese 日本------日本人(的)Mexico----Mexican 墨西哥————墨西哥人(的)France---French 法国——法语
China/PRC中国America/USA美国UK联合王国England英国Canada/CAN加拿大Australia澳大利亚New York纽约London伦敦Sydney悉尼
19.【十七节日(festivals)】:
New Year's Eve 除夕New Year 元旦Spring Festival 春节Lantern Festival 元宵节Dragon Boat Festival 端午节(龙舟节)the Mid-autumn Festival 中秋节Teathers' Day 教师节Christmas 圣诞节Thanksgiving Day 感恩节Halloween 万圣节Flay Day 国旗日20.【动词及短语(verbs)】:
look at 看着pass 传递get up 起床go to school 上学have lunch 吃午饭go home 回家watch TV 看电视go to bed 上床睡觉have breakfast 吃早饭have dinner 吃晚饭do 做play 玩,打(球)sleep 睡觉sing 唱歌give 给eat 吃fly 放(风筝)have got 拥有has got 拥有(have got的三单)go to work 上班Walk 步行swim 游泳live 居住go straight on 直着走turn left 向左转turn right 向右转write 书写take pictures 照相talk to 和、、、、、交谈play with 玩,摆弄listen to 听read 阅读let's=let us 让我们get on 上(车)get off 下(车)row 划(船)drink 喝,饮用want 需要,想要make 制作cook 烹饪,烧(菜)love 喜爱can 能够run 跑jump 跳ride 骑,乘Wash 洗,清洗draw 画visit 拜访,看望 e on 快点,赶快turn on 打开 e in 请进count 数数take 带走,拿走help 帮助learn 学习hope 希望study 学习find 找到bring 带来use 使用stay 停留suggest 建议borrow 借arrive 到达climb 攀登,爬finish 吃完hurry 赶紧,匆忙hurry up 快点wait 等待drop 落下,掉下meet 遇见need 需要understand 明白,理解argue 争吵wear 穿control 控制catch 接住,抓住hear 听到sit 坐sit down 坐下skip 跳(绳)ring 鸣,响feel 感觉到miss 想念tell 告诉lost 丢失smell 闻到cross 穿过should 应该hold 抓住say 说话,讲话collect 收集sound 听起来speak 说,讲(语言)believe 相信copy 模仿clean 清理show 展示,出示bee 成为shine 照耀fly away 飘走spend 度过be proud of 以。

自豪laugh 笑
cry 哭make a mistake 犯错误worry 担心stand up 起立do one's homework 做作业go swimming 去游泳play football踢足球, play basketball打篮球, play baseball 打棒球, play table tennis 打乒乓球, play puter games 打游戏, play chess下棋play the flute 吹笛, play the piano弹钢琴, play the trumpet 吹小号go to the park 去公园fly a kite 放风筝read a book 看书have a picnic吃野餐have a birthday party开生日聚会go out 出去send an e-mail 发邮件sing songs 唱歌have English/Chinese/Music 上英语(语文、音乐)buy 买go 去 e 来like 喜欢do 做dance 跳舞see 看见think 思考/想write 写watch 看ask 问love 喜欢know 知道help 帮助
21.【学科,科目(subject)】:
math 数学English 英语Chinese 汉语music 音乐art 艺术P.E 体育Science 科学physics 物理chemistry 化学biology 生物French 法语history 历史geography 地理project 综合实践
22.【形容词】
big 大的small 小的long 长的short 短的、矮的tall 高的fat 胖thin 瘦nice 好看的kind 和蔼可亲的funny 滑稽可笑的good 好的fine 好的happy 高兴的clean 干净的sad 难过的little 小的great 很好的new 新的old 老的,旧的young 年轻的busy 忙的sorry 遗憾的lovely 可爱的interesting 有趣的great 大的、美妙的difficult 困难的cute 可爱的fantastic 挺好的beautiful 美丽的favourite 最喜爱的
22.【指示代词】:
this 这个that 那个these 这些those 那些
23. 其他名词:
city 城市home 家room 房间classroom 教室school 学校teacher 教师student/pupil 学生birthday 生日homework 作业hobby 业余爱好word 词card 卡片question 问题answer 答案dollar 美元festival 节日game 游戏name 名字
24.【同音词】
我I—eye 眼喂hi—high高的小时hour—our 我们的for—four sun—son hear—here eight—ate right—write be—bee no—know nose—knows see—sea one—won there—their cent—sent aunt—aren’t
25.【反义词】
big---small long—short tall—short easy—difficult black—white old—new old—young right—left right—wrong sad—glad(happy) cold—hot thin—fat e—go same—different sit—stand bring—take light –heavy bright--dark
【对应词】
mum—dad brother—sister girl—boy here—there this—that east—westnorth—south day—night these—those
26.【完全、缩略形式】
I'm = I am he's = he is she's = she is they're = they are you're = you are we’re = we are it’s = it is there's = there is there’re = there ar e can't = can not don't = do not doesn't = does not isn't = is not aren't = are not let's = let us won't = will not
I'll = I will wasn't = was not weren’t = were not didn’t = did not couldn’t= could not 总结:通常情况下,'m即am, 's即is(但let's=let us), 're即are , n't即not (但can't=can not) 三、句型及语法
外研版第1册主要内容
句子:----Good morning! ----Good morning! ----Good afternoon! ----Good afternoon!
----How are you?----I’m fine, thank you.----What’s your name?----I’m ….
----Point to the door/window/blackboard…..----Stand up/ Sit down, please.
----What colour?----It’s red/blue….----How many? ----One/Two/Three….
----What’s this/that? ----It’s a chair/desk…----Happy birthday! ----Thank you.
---- Here’s your present/cake. ----Thank you. ----How old are you? ----I’m nine.
----Is it a cat? ----Yes, it is./ No, it isn’t.
----Where’s the cat? ---I don’t know./ It’s in the green bag.
----He/She’s a doctor/nurse…. ---- This is his/ her arm/head….
外研版第2册主要内容
词组:get up go to school have lunch go home watch TV go to bed have breakfast have dinner Spring Festival New Year fly kites go to work by bus by bike go fishing
句子:My favo urite toy is a car/ doll….
----What’s this/that? ----It’s a tiger.----What are they? ------ They’re lions.
I like/ don’t like football/ basketball….I like/ don’t like swimming/skipping….
----Do you like meat? ----Yes, I do./ No, I don/t.
----Does Daming/he/ she like bananas? -----Yes, he does./ No, she doesn’t.
I get up at seven o’clock.
----What’s the time, please? ---- It’s half past seven.
----What do you do at the weekend? ----- I play football.
----What does he/she do at the weekend? ---- He/ She watches TV.
Happy New Year.
It’s spring/ summer/ autumn/ winter.
It’s warm/hot/cool/cold in spring/summer/ autumn/ winter.
I’ve got a new book.
----Have you got a new book?--- Yes, I have. / No, I haven’t.
----Has Tom/he/she got a new book? ----Yes, he/she has. / No, he/she hasn’t.
Amy/ He/ She goes to school by bike/ by bus/by car.
It’s in/ on/ under the desk….
外研版第3-4册主要内容
一、情境问答:
第三册
1. Have you got_______? Yes, I have. No, I haven’t.
2. Excuse me. Where’s the________, please?
Go straight on. Turn right. Turn left.
3. What are you doing? I’m _______
What is he/she doing? He’s/She’s ___________
What are they doing? They’re __________
4. Do you want some _______? Yes, please. No, thank you.
5. Can you _____ ? Yes, I can. No, I can’t.
6. What are you going to do? I’m/We’re going to _______
7. Can I have some ______ ? Yes, you can. So rry, you can’t.
8. How many ____ are there in ____? There is/are______
第四册
9. Is it _____? Yes, it is. No, it isn’t.
10. Will you _____ ? Yes, I will. No, I won’t.
11. Was he/she/it _____? Yes, he/she/it was. No, he/she/it i sn’t.
Were you ______? Yes, I was. No, I wasn’t.
12. Did you/he/she/they____? Yes, I/he/she/they did. No, I/he/she/they didn’t.
二、词组短语
第三册
take pictures ________ watch TV________ read a book________ write a letter ________ listen to music________ talk to my friend________play with ________ in the park________ look at________row a boat ________ under the tree ________ play chess________ play football________play basketball ________ play table tennis________make a cake________ do the high jump________do the long jump________
第四册
have a picnic________ go swimming________ go to the park________do homework________ speak English________
情景运用:
第三册
1. 问路、指路
Excuse me. Where’s the _______, please? Go straight on. / Turn left. / Turn right. 2.询问对方正在做什么
What are you doing? I’m _______
What is he/she doing? He’s/She’s ___________
What are they doing? They’re __________
3. 询问对方是否要吃某种食物
Do you want some _______? Yes, please. No, thank you.
4. 询问对方的能力
Can you _____? Yes, I can. No, I can’t.
5. 谈论将要做的事情
What are you going to do? I’m/We’re going to _________
6. 向别人要东西吃
Can I have some ______ ? Y es, you can. Sorry, you can’t.
第四册
7. 介绍某人
This is_______
8. 谈论周一至周日将要做的事
What will you do on Monday? I’ll_______ on Monday
Will you ______ on Monday? Yes, I will. No, I won’t.
9. 做天气预报
It will be hot/cold/sunny/windy.
It will snow/rain.
10. 做比较
如: Sam is older than Daming.
外研版第5-6册主要内容
1.e back________
st Sunday/night/year________
3.go home________
4.go to school
5.go to the park________
6.hurry up________
7.in a hurry________
8.wait for ________
9.make a list ________ 10.shopping list________ 11.half a kilo________ 12.how many________ 13.how much________ 14.at the weekend________ 15.in the morning 16.in the afternoon________ 17.take a photo ________ 18.take photos________ 19.the British Museum________ 20.Big Ben________ 21.the Great Wall________ 22.the London Eye________ 23.give out________ 24.be careful ________25.too many________ 26.run fast________ 27.play football________ 28.half past seven________29.get up________ 30.sit down ________ 31.stand up________ 32.do morning exercises 33.play chess________ 34.on the farm________ 35.all day________ 36.of course________ 37.go out ________ 38.say hello to ________ 39.play basketball________ 40.play table tennis________41.many years ago________ 42.ten years ago________ 43.three days ago ________ 44. live in________
45.a lot of=lots of________ 46.watch TV________ 47.how about=what about________ 48.talk about________ 49.foreign language________ 50.study/work hard ________
51.an English teacher________ 52.a Chinese teacher________54.English/ Chinese food________53.by bus/plane/car/train/ship/bike________55.at school/.at home________ 56.at the library________ 57. library card________58.find out________59.be good at________ 60.look at________ 61.have /has got________62.in the east of China________ 63. in the west of China ________64. in the south of China ________ 65. in the north of China ________ 66.every year/day________ 67.send an email________ 68.a good idea________
69.listen to________ 70.be read for ________
1.Did your grandma learn English? Yes,she did. /No, she didn’t.
2.What did she have for breakfast? She had eggs and sausages.
3.Where are the books about…? They are on Shelf C.
4.When did you go to…? I went there in July.
5.What about chopsticks? It’s a good idea.
6.Why don’t you give him a kite ?
7.Did you…? Yes, I did. /No, I didn’t.
8.When did you e back ? We came back last Sunday.
9.How many bananas do you want? Six,please.
10.How much chess do you want? Half a kilo.
11.Do you like…? Yes,I do. /No,I don’t.
12.Where did you go ? We went to the British Museum.
13.What did you do at the weekend? We visited lots of places.
14.What’s the matter?
15.Whose bag is this ? It’s Lingling’s.
16.Is this your cap? Yes, it’s mine.
17.There be+ 某物+某地
18.Can you…? Yes, I can. /No, I can’t.
19.What time do you get up? I get up at half past six.
外研版第7-8册主要内容
第七册
1.These postcards are great! It’s a picture of the Great Wall. Tell me more about the Great Wall.
How long is it?
2.There’s a Chinatown in New York! There are lots of Chinese shops and restaurants there.
3.I’ve got lots o f stamps. These are some stamps from Canada. This stamp is from China.
4.Thanksgiving is my favourite festival. We always have a special meal.
5.Can you speak English? Can I write to your friend?
6.Daming has got a Chinese kite and we fly it in the park. I’ve go t some chopsticks, but they are
difficult.
7.Pandas eat for twelve hours a day. X|k | B| 1 . c| O |m
8.Do you often play with dolls? Do you often clean your room?
9.Do you want to visit the UN building in New York?
10.Don’t talk in the library. Please stand in lin e.
第八册
1.What do you want to eat? I want a hot dog, please. How much is it? It’s thirteen dollars and
twenty-five cents.
2.When are we going to eat? We’re going to eat at half past twelve. It’s going to snow in
Harbin.
3.The sun is shining. The birds are singing in the trees. The ducks are eating our picnic.
4.Who can help me? Sorry, I can’t. I’m making Daming’s birthday card. I can help you.
5.Daming is having a birthday party. Daming is playing the trumpet, but the phone is ringing.
6.I brought you this book. Who gave it t o you? Simon’s family gave it to me.
7.Shenzhou V flew into space with Yang Liwei. He spent about twenty-one hours in space. He
made a video and now he is very famous.
8.Helen Keller became blind and deaf. She couldn’t see and she couldn’t hear. Later sh e could
read and write. She wrote a book about herself.
9.what’s the matter? Why are you laughing? Why are you wearing a raincoat? Because it’s
going to rain.
10.Are you going to go to middle school this September? Yes. I’m really excited. What are you
going to study?
问:它们能以什么样的形式做功?
学生:风能吹动船帆使船航行,对船做功。

流动的水能推动水轮机转动,对水轮机做
功。

教师:这位同学表述的很清楚,大家能不能给他一点掌声啊?
教师:在我们的生活经验中还有那些物体也能够做功的?每一小组一边讨论一边写在
纸上,看看那一组写的多?
3 分钟后,让学生展示,教师小结:如果一
个物体能够对另一个物体做功,这个物体
就具有能量。

教师:我们今天学习能量中的一种即机
械能。

板书:第三章第四节机械能
出示两张图片,
教师问:高速行使的列车和奔跑中的刘翔具有能量吗?
学生:具有
教师:列车和刘翔有什么共同特点?
学生:运动。

教师:这种运动的物体具有的能量叫动能
板书:运动的物体具有的能量叫动能
教师:在我们生活中具有动能的物体有那些?
小组讨论,展示,教师小结。

教师:动能有大有小,那么动能大小怎样来衡量?
学生:通过做功的多少啊?
教师:不错,动能越大,对其他物体做的功就越多。

反之则小。

通过这种方法,每一小组在阅读课
本77 页基础上设计一个实验来探究影响动能
大小的因素。

学生展示,教师评价,这些实验让学生课后完成,打出幻灯片。

教师:老师在这里设计了一个实验,大家按照这个实验来探究一下上述的问题。

(每一小组实验,汇报结果)
总结:物体动能的大小与它的质量和运动速度都有关系。

质量越大,速度越大,物体的动能越大。

板书:物体动能的大小与它的质量和运动速度都有关系。

质量越大,速度越大,物体的动能越大。

教师:运动的物体具有动能,那么下列两种物体是否具有能量。

学生实验:压缩弹簧,沙袋打击四角钉有长钉的木
板。

教师:在这里弹簧,沙袋发生了什么变化?
学生:弹簧被压缩,沙袋被举高
教师:被压缩的弹簧和举高的沙袋是否具有能量?为什么?
学生:具有能量,因为它们能够做功对其它物体。

教师:我们把这一类物体所具有的能量叫做势能小结、板书:发生弹性形变或者被举高的物体所具有
的能量叫做势能。

教师:发生弹性形变的物体所具有的能量又叫做弹
性势能
被举高的物体所具有的能量又叫做重力势能,
动能和
势能都归属于机械能。

一个物体既可以拥有动
能同时也可以拥有势能。

(总结)五、板书设计
第三章第四节机械能
一、动能
运动的物体具有的能量叫动能
二、势能
发生弹性形变或者被举高的物体所具有的能量叫做势能。

1、发生弹性形变的物体所具有的能量又叫做弹性势能
2、被举高的物体所具有的能量又叫做重力势能
动能和势能都归属于机械能。

六、课堂练习
1)高山上有一块大石头,稳稳地待在那里,它有没有能
量?有什么能量?
(2)列举几个物体具有动能、重力势能、弹性势能的
事例。

(3)猜想一下机械能的单位
机械能(第二课时)
一、教学目标
(一)知识目标:
1、知道影响势能大小的因素。

2、理解动能、势能的相互转化。

3、了解机械能的单位
(二)技能目标:
1、熟练掌握控制变量法等科学探究的方法。

2、通过活动培养科学探究的能力。

(三)情感目标:
1、让学生在科学探究知识的过程中养成敢于探究的意识
和敢于创新的精神。

2、在小组中,养成与人和谐共处,协作学习的习惯。

二、重点和难点
响势能大小的因素,动能、势能的相互转化,科学探究。

三、教具:
铁支架,长木板,滑块,重物,定滑轮、多媒体,单罢。

四、教学过程设计:
引入:上堂课我们讲过动能有大小之分,那么势能有没有大小之分呢?毫无疑问是有的,那怎样去区分它的大小呢?
学生:也可以通过做功的大小
教师:确实可以,接下来我们一起来探究一下重力势能。

打出幻灯片,解释实验,探究问题,得出结论。

总结、板书:物体被举得越高,质量越大,它的重力势能也越大。

而弹性势能的大小与形变有关,形变越大弹性势能就大,反之就小。

教师:现在我们已经了解了动能和势能,并且知道它们都属
于机械能,在国际单位制中它们的单位是焦耳,简称焦,
符号J。

那么它们之间有没有联系呢?
[计算机演示]小球从从圆弧轨道的一端滑向另一端的过程。

问:小球在最高点时动能和势能是怎样的?
学生:动能为零,势能最大。

问:在下滑过程中,动能和势能发生了什么样的变化?
学生:动能逐渐增加,势能逐渐减少。

问:在最底点时,动能和势能是怎样的?
学生:动能最大,势能最小
问:在向上滑过程中,动能和势能发生了什么样的变化?
学生:动能逐渐减少,势能逐渐增加。

问:在另一端的最高点时,动能和势能是怎样的?
学生:动能为零,势能最大。

教师:猜想一下,两边的端点是否一样高。

学生:一样。

教师:再猜想一下,在整个过程中,动能和势能有什么联系?学生:可能是动能和势能在转化,势能转化为动能,动能转化
为势能。

教师:再猜想一下,在整个过程中,动能和势能之和会发生增加和减少吗?
学生:可能不会发生改变,因为两个端点是一样高的。

教师:这就是机械能可以相互转化,并且转化过程中机械能是守衡的。

即机械能的总和保持不变。

[学生实验]观察单摆的摆动。

并且分析整个过程,写在纸上,进行交流。

教师归纳:
分析:
A 点:由于被举高而具有重力势能。

A 到O:高度逐渐减小,重力势能
随之减小;运动速度逐渐增大,动能

之增大。

重力势能转化为动能。

O 点:高度最低,重力势能最小;
速度最快,动能最大。

O 到B:速度逐渐减小,动能随之
减小;高度逐渐增大,重力势能
随之增
大。

动能转化为重力势能。

B 点:速度最慢,动能最小;高度
最高,重力势能最大。

教师小结:在空气中,因为受到空气的阻力的作用,能量逐渐
消失,单罢的罢幅会逐渐减少,最后停止。

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