日本成人片在线_久久免费精品视频_国产午夜精品久久久久久免费视_校花撩起jk露出白色内裤国产精品_av影片免费在线观看_国产小视频在线看_最新av免费在线观看_99久久99久久精品国产片_欧美成人猛片aaaaaaa_蜜桃免费网站一区二区三区

【題目】兩個完全相同的條形磁鐵,放在平板AB上,磁鐵的NS極如圖所示,開始時平板及磁鐵皆處于水平位置,且靜止不動。

a現(xiàn)將AB突然豎直向上平移平板與磁鐵之間始終接觸,并使之停在A″B″處,結(jié)果發(fā)現(xiàn)兩個條形磁鐵吸在了一起。

b如果將AB從原來位置突然豎直向下平移,并使之停在位置A′B′處,結(jié)果發(fā)現(xiàn)兩條形磁鐵也吸在了一起,請回答下列問題:

1開始時兩磁鐵靜止不動,磁鐵間的相互作用力是________力;右側(cè)的磁鐵受到的靜摩擦力的方向向________

2a過程中磁鐵開始滑動時,平板正在向上加速還是減速呢?答:________

3b過程中磁鐵開始滑動時,平板正在向下加速還是減速呢?答:________

【答案】1吸引 2減速 3加速

【解析】1磁鐵靜止時,二者間的相互吸引力與靜摩擦力大小相等,對右側(cè)的磁鐵來說,吸引力向左,靜摩擦力向右。2當(dāng)平板向上運(yùn)動而磁鐵吸在一起時,說明摩擦力減小,磁鐵所受支持力減小,磁鐵應(yīng)處于失重狀態(tài),所以平板應(yīng)向上減速運(yùn)動,加速度方向向下。3當(dāng)平板向下運(yùn)動而兩磁鐵吸在一起時,磁鐵應(yīng)處于失重狀態(tài),所以加速度仍向下,故是向下加速運(yùn)動。

練習(xí)冊系列答案
相關(guān)習(xí)題

科目:高中地理 來源: 題型:

【題目】III. 短文改錯

假定英語課上老師要求同桌之間交換修改作文,請你修改你同桌寫的以下作文。文中共有10處語言錯誤,每句中最多有兩處,每處錯誤僅涉及一個單詞的增加、刪除或修改。

增加:在缺詞處加一個漏字符號(),并在其下面寫出該加的詞。

刪除:把多余的詞用斜線(\)劃掉。

修改:在錯的詞下劃一橫線,并在該詞下面寫出修改后的詞。

注意:

1.每處錯誤及其修改均限一詞;

2.只允許修改10處,多者(從第11處起)不計分。

I am travelling back with my parents from seeing my grandparents then it started to snow. At first, I thought it was fun and everything looked beautifully. I was looking forward to make a snowman in the playground at school the next day, and suddenly the car drove off road and into a channel. My father called the rescue team, but they said that would be a long time before they could reach us. However, we sang songs and told stories to pass the time. Several hour later, the rescue team pulled their car out of the channel. At last, we managed to drive very slowly to home. I would never forget this experience.

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】選詞填空

用下列詞組的適當(dāng)形式完成下列句子

fast asleep vary from to… take sb. by surprise freeze over

draw up give birth to make one’s way take notice

have a gift for burn to the ground

1. The air temperature was well below freezing, and lakes and rivers __________.

2. Having spent the whole morning climbing Mount. Tai, the family were very tired and slowly ____________ to

the hotel.

3. He was lying ____________ on the sofa; it would be cruel to wake him.

4. His heart attack was so sudden that I think even the doctors were ____________.

5. The story The Pity of Zhongyong concerns a boy who _______________ writing poetry in his childhood.

6. The outbreak of H7N9 bird flu has really made the government sit up and ___________.

7. The film If You Are the One ______________ a TV show of the same name.

8. After a heated discussion, they __________ a plan to advertise their new product nationwide.

9. The bus was ___________, and at least 30 people burnt to death.

10. The land of Changbaishan ______ in height ____ 700 metres above sea level __ over 2,000 metres.

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】A

The first ancient Olympic Games for which we still have written records were held in 776 BC. Coroebus won the only event at the Olympics. This made him the very first Olympic champion in history. Then they grew and continued to be played every four years. In 393 AD, the Roman emperor Theodosius , a Christian, announced to end the Games because of their pagan (異教的) influences.

About 1,500 years later, a young Frenchman named Pierre de Coubertin began their revival (恢復(fù)). In 1892 Coubertin first brought forward his idea to revive the Olympic Games but failed.

Two years later, Coubertin organized a meeting with 79 delegates (代表) who represented nine countries. At this meeting he got what he wanted. All the delegates at the conference voted for the Olympic Games. They also decided to have Coubertin set up an international committee to organize the Games. This committee became the International Olympic Committee (IOC) and Demetrious Vikelas from Greece was selected to be its first president. Athens was chosen for the revival of the Olympic Games and the planning was begun.

The very first modern Olympic Games opened in the first week of April, 1896. Since the Greek government had been unable to afford a stadium, a rich Greek architect, Georgios Averoff, donated one million drachmas (over $100,000) to repair the Panathenaic Stadium, originally built in 330 BC.

Since the Games were not well publicized internationally, contestants (選手) were not nationally chosen but rather came individually and at their own expense. Some contestants were tourists who happened to be in the area during the Games.

【1】What would be the best title for the passage?

A. The History of the Olympics

B. How Coubertin Set up IOC

C. The First Modern Olympic Games

D. Great Changes in the Olympic Games

【2】 Coubertin held a most important meeting with 79 delegates in______________.

A. 1500 B. 1892

C. 1894 D. 1896

【3】 Who offered money to help the first modern Olympic Games?

A. Demetrious Vikelas.

B. Coroebus.

C. Pierre de Coubertin.

D. Georgios Averoff.

4At the first modern Olympic Games, ______________.

A. winners were given money as prize

B. IOC invited contestants to tour Greece

C. there were no strict rules for being a contestant

D. many countries chose some athletes to compete

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】A

In 1995, Oseola McCarty gave a present of $ 150,000 to the University of Southern Mississippi. She wanted to help poor students. It was a very generous thing to do. But her friends and neighbors were surprised. McCarty was a good woman. She went to church. She was always friendly and helpful. But everyone in her town knew that McCarty was not rich. In fact, she was poor.

How did a poor 86-year-old woman have so much money? Oseola McCarty was born in 1908 in Hattiesburg, Mississippi. She had to leave school when she was eight years old to help her family. She took a job washing clothes. She earned only a few dollars a day. Oseola washed the clothes by hand. Then she hung the clothes to dry. She did this for nearly 80 years. In the 1960s she bought an automatic washer and dryer. But she gave them away. She did not think they got the clothes clean enough! At that time, many people started to buy their own washers and dryers. McCarty did not have much work, so she started to iron clothes instead.

McCarty never married or had children. Her life was very simple. She went to work and to church. She read her Bible. She had a black-and-white television. But she did not watch it very much. It had only one channel.

McCarty saved money all her life and eventually had about $250,000.When she was 86, a lawyer helped her make a will. She left money to the church, her relatives, and the university. McCarty just wanted to help others. She did not think she was a special person. But then people found out about her present to the university. She received many honors(榮譽(yù)). She even flew in an airplane for the first time! Oseola McCarty died in 1999.She was a shy and ordinary woman who became famous.

【1】Oseola McCarty gave $150,000 to the University of Southern Mississippi __________.

A. to help the poor students

B. to surprise her friends and neighbors

C. to show her generosity

D. to be a good and rich woman

【2】From the story we know ___________.

A. McCarty was born in a poor family near the University of Southern Mississippi

B. everyone was surprised because they thought McCarty had no education

C. washers and dryers brought a change in McCartys life

D. McCarty gave half of her money to the church and her relatives.

【3】 Which of the following is true?

A. McCarty had to work to help her family after school every day.

B. McCarty learned to read the Bible by herself in the school.

C. McCarty made one third of her money by washing and ironing clothes.

D. McCarty did not have her own family because she had no husband or children.

【4】 From which of the following can we tell McCarty lived a simple life?

A. She worked hard all her life.

B. She didn’t think she was special.

C. She didn’t have many interests.

D. She had a TV set with many channels.

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】如圖所示是一種利用電磁原理制作的充氣泵的結(jié)構(gòu)示意圖其工作原理類似于打點(diǎn)計時器,當(dāng)電磁鐵通入電流時,可吸引或排斥上部的小磁鐵,從而帶動彈性金屬片對橡皮碗下面的氣室施加力的作用,達(dá)到對外充氣的效果請回答以下問題:

1當(dāng)電流從電磁鐵的接線柱a流入時,發(fā)現(xiàn)吸引小磁鐵向下運(yùn)動,則電磁鐵的上端為________極,小磁鐵的下端為________極

2你認(rèn)為這種充氣泵是利用直流電好,還是利用交流電好?答案:________

3纏繞電磁鐵用的鐵芯可分為硬磁性材料和軟磁性材料硬磁性材料在磁場撤去后還會有很強(qiáng)的磁性,而軟磁性材料在磁場撤去后就沒有明顯的磁性了你認(rèn)為這種鐵芯最好用________材料制作

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】短文改錯

假定英語課上老師要求同桌之間交換修改作文,請你修改你同桌寫的以下作文。文中共有10處語言錯誤,每句中最多有兩處。錯誤涉及一個單詞的增加、刪除或修改。

增加:在缺詞處加一個漏詞符號(),并在其下面寫出該加的詞。

刪除:把多余的詞用斜線(\)劃掉。

修改:在錯的詞下劃一橫線,并在該詞下面寫出修改后的詞。

注意:

1. 每處錯誤及其修改均僅限一詞;

2. 只允許修改10處,多者(從第11處起)不計分。

It was the International Womens Day. Li Hua had a good idea and tells his father that he was going to do everything to celebrate it. He asked his father to help him. First they decided to do some housework, that was always done by his mother. Li Hua cleaned the house completely while his father did some shop. Then they made a good meal, cooking fish, pork, chicken, soup but some other delicious dishes. Li Hua laid the table and set a vase full with flowers in the middle of the table. After that they hid them behind the door and waited the mother in order to give her a surprise. When his mother came back and saw the delicious food, she felt happily.

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】聽下面一段對話,完成五道小題,每小題填寫一個詞這段對話你將聽兩遍。

查看答案和解析>>

科目:高中地理 來源: 題型:

【題目】化學(xué)興趣小組為探究SO2的性質(zhì),按下圖所示裝置進(jìn)行實(shí)驗(yàn)。(已知:Na2SO3+H2SO4===Na2SO4+SO2↑+H2O)

請回答下列問題:

(1)裝置A中盛放濃硫酸和亞硫酸鈉的儀器名稱分別是________、________。

(2)反應(yīng)后,裝置B中發(fā)生的現(xiàn)象是_________________________________;反應(yīng)的離子方程式為______________________________;裝置C中的現(xiàn)象是___________________________,表現(xiàn)了SO2的________;裝置D中現(xiàn)象是_____________________________________________,發(fā)生反應(yīng)的化學(xué)方程式為_________________________________________。

(3)裝置E的目的是探究SO2與品紅作用的可逆性,請寫出實(shí)驗(yàn)操作及現(xiàn)象_________________________。

(4)F裝置的作用是________________________,漏斗的作用是___________________________。

查看答案和解析>>

同步練習(xí)冊答案
精品欧美久久| 中文字幕永久有效| 黄色片一级视频| 亚洲国产成人va在线观看麻豆| 久久久精品视频国产| 精品无码在线视频| 国产精品成人免费观看| 免费视频久久久| 欧美一级一区二区三区| 国产在线一二三区| bl在线肉h视频大尺度| 99er精品视频| 久久伦理在线| 巨乳诱惑日韩免费av| 国产成人精品影视| 亚洲女人的天堂| 欧美三级三级三级爽爽爽| 亚洲国产精品久久精品怡红院 | 中文字幕国产亚洲| 2019中文字幕免费视频| 国产精品视频免费一区二区三区| 好吊色这里只有精品| 一级片视频免费观看| 91香蕉视频污在线观看| 一本色道久久综合无码人妻| 欧美xxx.com| 国产精品av一区二区三区| 色狼人综合干| 久久精品二区三区| 久久亚洲捆绑美女| 欧美亚洲国产怡红院影院| 亚洲天堂精品在线| 国产精品青草久久久久福利99| 欧美成人蜜桃| 在线看的黄色网址| 精品无码久久久久成人漫画| 99久久国产热无码精品免费| 欧美成人性生活视频| 色综合一区二区日本韩国亚洲| 成人亚洲一区| 国产精品综合视频| 亚洲成人精品一区二区| 国产丝袜一区视频在线观看| 国产精品旅馆在线| 国产911在线观看| 日本黄色动态图| 一区二区乱子伦在线播放| 国产视频精品久久| 亚洲小说春色综合另类电影| 国产亚洲精品久久久久婷婷瑜伽| 久久久亚洲精品一区二区三区| 欧美日韩综合在线| 久久频这里精品99香蕉| 先锋影音日韩| 怡红院一区二区| 中文天堂在线资源| 美女黄视频在线观看| 风间由美一区二区av101 | 一区二区三区91| 亚洲人成自拍网站| 成人在线视频电影| gogogo高清免费观看在线视频| 黄色一级视频在线观看| 中文在线三区| 日韩在线观看中文字幕| 日本在线不卡视频一二三区| 亚洲制服丝袜一区| 中文字幕日韩av电影| 久久精品日产第一区二区三区| 四季av一区二区三区| 日韩在线视频免费播放| av在线电影院| 日本妇女一区| 福利电影一区二区| 宅男在线国产精品| 国产男人精品视频| 热久久精品免费视频| 亚洲天堂日韩av| 九色porny丨首页在线| 国产99久久精品一区二区300| 国产成人午夜99999| 欧美精品久久天天躁| 国产精品大陆在线观看| 女人扒开屁股爽桶30分钟| 国产对白videos麻豆高潮| 亚洲欧美视频一区二区| 欧美精品一区二区三区精品| 久久综合成人精品亚洲另类欧美 | 欧美另类暴力丝袜| 2021国产视频| 久草成人在线视频| 老司机在线永久免费观看| 欧洲杯半决赛直播| 国产精品欧美精品| 久久精品国产综合| 成人毛片100部免费看| 台湾亚洲精品一区二区tv| av剧情在线观看| 欧美激情视频一区二区三区在线播放 | 欧美成人三区| 欧美成熟视频| 亚洲成人激情综合网| 97超级碰碰人国产在线观看| 麻豆tv在线播放| www.国产色| 都市激情亚洲一区| 日韩国产成人精品| 欧美高清视频一二三区| 91久久嫩草影院一区二区| 国产又黄又嫩又滑又白| 成人午夜免费在线观看| 色悠久久久久综合先锋影音下载| 国产99久久久国产精品免费看| 精品国产污网站| 欧美日韩一区二| 亚洲aaa视频| 米奇精品一区二区三区| 在线欧美不卡| 欧美日韩一区国产| 波多野结衣久草一区| 97伦伦午夜电影理伦片| 国产中文字幕在线| 激情欧美国产欧美| 欧美午夜理伦三级在线观看| 91亚洲国产成人久久精品网站| xxxx黄色片| 成全电影播放在线观看国语| 欧美日韩国产亚洲一区| 91国偷自产一区二区开放时间 | 日韩欧美在线一区二区三区| 久久亚洲国产精品日日av夜夜| 999久久久国产| 香蕉久久aⅴ一区二区三区| 免费日韩av片| 精品少妇一区二区三区免费观看| 日韩高清三级| 欧美亚韩一区二区三区| 粉嫩一区二区三区| 成人激情免费网站| 欧美另类高清videos| 亚洲精品www.| 青春草在线观看| 韩国av一区| 欧美一级片在线| 视频一区二区精品| 国产精品va无码一区二区三区| 日本综合视频| 久久精品夜夜夜夜久久| 97视频免费观看| 蜜臀av粉嫩av懂色av| av在线电影免费观看| 久久亚洲风情| 亚洲欧美在线第一页| 精品久久久久久久久久中文字幕| 国产三级自拍视频| 成人影院在线| 欧美视频一区二区在线观看| 日本精品一区二区| 乱子伦一区二区三区| 六月丁香久久丫| 日韩欧美在线看| 欧美日韩综合另类| 一级特黄免费视频| 国产一区网站| 欧美日韩和欧美的一区二区| 亚洲一卡二卡区| 国产男男gay体育生白袜| 成人三级视频| 欧美一区二区久久| 青青视频免费在线观看| 精品国产亚洲av麻豆| 久久精品一区二区不卡| 日韩美一区二区三区| av在线免费观看国产| 丁香六月色婷婷| 国产精品草草| 亚洲欧美中文日韩在线v日本| 欧美xxxxx在线视频| 青青草视频在线观看| 麻豆91在线播放免费| 不卡av在线网站| 日本人添下边视频免费| 激情在线视频播放| 久久久精品黄色| 亚洲在线免费看| 中文字幕视频网站| 精品精品99| 欧美tickling网站挠脚心| 欧美精品99久久| 久久久久久青草| 国产一区二区视频在线播放| 久久人91精品久久久久久不卡| 深爱五月激情网| 粉嫩av一区二区三区四区五区 | 在线麻豆国产传媒1国产免费| 在线日韩视频| 色哟哟入口国产精品| 亚洲成年人在线观看| 麻豆理论在线观看| 综合av第一页| 日本成人三级| 天天干视频在线观看| 日韩av中文字幕一区二区三区| 久久视频在线播放| 美女被到爽高潮视频| 亚洲精品毛片| 在线视频一区二区三区| 久久久久99精品成人片| 欧美黄色小说| 成人18视频在线播放| 91综合免费在线| 中文字幕一区二区人妻视频| 久久久久国产| 日韩中文字幕国产| 91精品人妻一区二区三区蜜桃欧美| 久久xxx视频| 欧美性xxxxxxx| 国产精品专区在线| 免费高清在线观看| 欧美国产1区2区| 热re99久久精品国产99热| 成人毛片在线精品国产| 免费人成精品欧美精品| 日韩av电影中文字幕| 日韩无码精品一区二区三区| 羞羞答答成人影院www| 俺去亚洲欧洲欧美日韩| 亚洲色图27p| 精品国产一区二区三区av片| 亚洲免费视频一区二区| 韩国无码一区二区三区精品| 日韩精品视频在线看| 欧美成人乱码一区二区三区| 国产麻豆剧传媒精品国产| 精品久久在线| 欧美一级日韩不卡播放免费| 色婷婷一区二区三区在线观看| 高清电影一区| 欧美区一区二区三区| 不卡中文字幕在线观看| 久久天堂av| 欧美日韩一区二区三区不卡| 日本三级黄色网址| 成人啊v在线| 欧美三区免费完整视频在线观看| 天堂中文视频在线| 91亚洲视频| 日韩一区二区三区高清免费看看| 91人妻一区二区| 盗摄牛牛av影视一区二区| 日韩麻豆第一页| 精品一区二区三孕妇视频| 大片网站久久| 久久久久九九九九| 精品国产乱子伦| 免费视频最近日韩| 2022国产精品| 中文字幕一二三区在线观看| 久久久久久毛片| 日韩中文在线字幕| 超碰在线网站| 欧美午夜电影网| 久久久久亚洲AV成人网人人小说| 91精品尤物| 综合久久五月天| 国产网友自拍视频| 久久久精品午夜少妇| 91久久极品少妇xxxxⅹ软件| 精东传媒在线观看| 国产精品理伦片| 久草热视频在线观看| jizzyou欧美16| 亚洲经典中文字幕| 色在线观看视频| 亚洲在线电影| 国产精品初高中精品久久| 日韩精品系列| 亚洲图片自拍偷拍| 加勒比av中文字幕| 欧美一性一交| 久久久爽爽爽美女图片| 国产乱色精品成人免费视频 | 亚洲国产精品天堂| 999在线观看| 日本成人7777| 国模极品一区二区三区| 国产情侣av在线| 久久综合999| 国产婷婷一区二区三区| 美女视频一区| 色av中文字幕一区| 欧美精品一二三四区| 国产精品一区二区你懂的| 亚洲日本精品一区| 周于希免费高清在线观看| 精品国产伦理网| 久久香蕉精品视频| 久久97超碰国产精品超碰| 亚洲第一综合| 天天免费亚洲黑人免费| 亚洲男人的天堂网站| 特级毛片www| 成人爱爱电影网址| 岛国大片在线播放| 国产精品一区二区三区四区在线观看 | 青青青青在线| 欧美电影一区二区| 日韩精品一区二区三区在线视频| 亚洲一区成人| 日韩视频专区| 欧美黑人粗大| 精品国偷自产在线视频99| 国产精品欧美综合亚洲| 中文字幕免费不卡在线| 色天使在线观看| 日韩精品影视| 69堂成人精品视频免费| 97caopor国产在线视频| 精品久久久久久久一区二区蜜臀| 国产在线观看成人| 粉嫩绯色av一区二区在线观看| 黄色片网址在线观看| 成人h动漫免费观看网站| 88xx成人精品| 香蕉97视频观看在线观看| 欧洲一区二区av| 91高清免费观看| 寂寞少妇一区二区三区| a级免费在线观看| 精品一区二区男人吃奶| 国产精品h片在线播放| 99re热久久这里只有精品34| 欧美一区二区三区四区五区| 国产91av视频| 国产日韩欧美综合在线| 日本特黄在线观看| 亚洲国内欧美| 一区不卡字幕| 成人h动漫精品一区二区器材| 国产成人在线一区二区| 日本成人网址| 日韩精品免费一线在线观看| 国产精品美女一区| 亚洲一区在线观看免费观看电影高清| 国产ts丝袜人妖系列视频| 日本大胆欧美人术艺术动态| 欧美黑人在线观看| 精品一区三区| 国产高清在线精品一区二区三区| 日本乱码一区二区三区不卡| 久久精品国产视频| 伊人75在线| 日韩精品专区在线影院观看| 亚洲一级视频在线观看| 亚洲影院在线观看| 日本成人精品视频| 91在线观看高清| 黄页网站在线看| 日韩高清在线电影| 少妇高潮喷水久久久久久久久久| 久久精品国产www456c0m| 欧美日韩精品免费看| 国产视频网站一区二区三区| 国产精品免费网站| 国产白丝在线观看| 欧美日本精品在线| 午夜小视频在线| 中文字幕精品av| 三级视频网站在线| 亚洲精品国精品久久99热 | 三级黄色片免费观看| 香蕉久久国产| 国内性生活视频| 韩国欧美一区| 久久亚洲精品无码va白人极品| 成人中文在线| 在线视频欧美一区| 精品国产乱码久久久| 日本不卡二区高清三区| 乱亲女h秽乱长久久久| 美女黄毛**国产精品啪啪| 凹凸成人在线| 精品久久中出| 国产suv精品一区| 精品久久久久久中文字幕动漫 | 欧美5-7sexvideos处| 日韩av中文字幕在线免费观看 | 亚洲综合清纯丝袜自拍| 国产精品99精品无码视| 一区二区成人在线| 久久久精品视频免费| 亚洲一区av在线| 中文字字幕在线中文| 狠狠躁夜夜躁久久躁别揉| 日韩一级片中文字幕| 色哟哟一区二区| 国产精品探花视频| 6080亚洲精品一区二区| 免费看av毛片| 亚洲成人精品av|