关于介绍机翼的介绍作文?

一、关于介绍机翼的介绍作文?

飞机作文(1)

  飞机的机翼的上下两侧的形状是不一样的,上侧的要凸些,而下侧的则要平些。当飞机滑行时,机翼在空气中移动,从相对运动来看,等于是空气沿机翼流动。由于机翼上下侧的形状是不一样,在同样的时间内,机翼上侧的空气比下侧的空气流过了较多的路程(曲线长于直线),也即机翼上侧的空气流动得比下侧的空气快。根据流动力学的原理,当飞机滑动时,机翼上侧的空气压力要小于下侧,这就使飞机产生了一个向上的升力。当飞机滑行到一定速度时,这个升力就达到了足以使飞机飞起来的力量。于是,飞机就上了天。  说的再直观点:上表面数据一律假设为1,下表面一律假设为2。

  则:机翼上表面长度为s1,下表面为s2,上表面和下表面在空气中移动的时间一定,设为t,t1=t2,由此可以得出:v1=s1/t1 v2=s2/t2 s1>s2 t1=t2,所以:v1>v2,根据帕奴利定理——“流体对周围的物质产生的压力与流体的相对速度成反比。”,因此上表面的空气施加给机翼的压力f1小于下表面的f2。f1、f2的合力必然向上,这就产生了升力。

  莱特兄弟真厉害。

二、关于lisa的介绍作文?

lisa是韩国女团的舞蹈担当,精通多国语言,人美心善

三、关于介绍平房的作文?

我家从平房搬到楼房已近三年了,但我却常常忆起住过的那两间平房,忆起在平房生活的时光———那美丽幸福的时光。我经常带着女儿去看看那座平房,虽然它现在已经拆了,只剩一堆残砖碎瓦,狼藉满目。但是我感谢那两间平房,因为那是我在外多年漂泊后安下的第一个家。在那里,有我温馨的回忆;在那里,我娶了美丽贤惠的妻子,有了活泼可爱的女儿,在近五年的时光里,我们留下了无数的情趣、快乐、温馨。

  我们那个家非常简陋。两间平房是70年代盖的,里面的墙皮整片地往下掉。一个小院仅有十几平米大,小院南边是一条小路,隔着小路是一间五六平方的厨房,厨房隔壁是我自己盖的一间堆放杂物的小房子。

  平房的面积很小,两间合起来大约有三十平米。一进门的一间算是客厅,但也兼有卧室、饭厅等功能。靠西面,放了一个三人的红色皮沙发,中间是茶几,靠东面是一组低柜,上面放了一台25英寸的电视。北边靠墙是一张单人床,是母亲来看孙女时睡的。南面靠左是冰箱,里面一间是我们的卧室,有一张床和两个衣橱。所有家当仅此而已。

那是幸福的小屋,将工作的劳累、烦恼一并忘却;节假日,我们就在家打扫卫生,整理东西,将小屋布置得整洁。那麼多年我还常常忆起小屋里那局促而有趣的生活

四、关于介绍南京的作文?

你好,我是【fihzh17235】,很高兴为你解答。我的家乡南京  我的家乡在六朝古都南京,一个有山有水的地方。那儿山清水秀,古巷老街所处可见。大街小巷里有许多艺人,更有无数美味佳肴。  南京的小笼包和鸭血粉丝汤是二大特色,还有一句俗语“轻轻移,慢慢提,前开窗,后喝汤”来讲述小笼包的吃法呢。  南京的民间艺人更是数不胜数。有糖稀画、捏面人、吹糖艺、做棉花糖的,还有冰糖葫芦,现在还有冰糖苹果和冰糖水果呢!  著名的夫子庙里有许多小吃店。里面有臭豆腐店,板栗店,还有卖状元豆、酒酿元宵的店。最受欢迎的是板鸭和盐水鸭,还有一种特别的“叫花子鸡”,是包了一层泥土的鸡,但很多人都排上好久的队去买。  最出名的是南京的老吆喝。从小我就是听着它长大的,有一句让我记得最牢“磨剪子嘞,锵菜刀”,往楼下一看,总能看见一位老爷爷肩上挎着一条长板凳,板凳上有一块磨刀石,方便随时为顾客磨刀。元宵节前后,又常会听见一句关于元宵的吆喝:“卖酒酿,桂花酒酿卖了。”  南京的民风民俗是如此的多,恐怕只有老一辈南京人才知道,但是如果介绍名胜古迹,谁都一定会知道。  玄武湖中有五个小岛:环洲、樱洲、翠洲、梁洲、菱洲。湖边有许多垂柳,曾有诗人写下这样一句话“无情最是台城柳,依旧烟笼十里堤”。  我的家乡在南京,拥有六朝古都的历史,有山有水的好地方!更多专业的科普知识,欢迎关注我。如果喜欢我的回答,也请给我赞或转发,你们的鼓励,是支持我写下去的动力,谢谢大家。

五、关于网络介绍的英语作文?

Inernet has been an important part in our life.With the help of Inernet we can develop the effective of our study or job.For example ,we can learn more knowledge about the world from the Inernet.

And as the youngs in 21st centery,the skill of using the Internet has been the most necessary point for us.But there are risks in it.A lot of youngners lost themselves in the data world and can not catch up with others in study.

They’d like to be the best in the games instead of in hard-working.In my own point,I think Internet has more advantages than disadvantages.People should make the most use of it so that it can been useful not harmful.

六、关于介绍莆田的英语作文?

My home is beautiful putian, in that we can see the beautiful Haihe River, she has been extended to the east of putian,

七、关于雷州介绍的英语作文?

Leizhou, a county-level city under the jurisdiction of Guangdong Province, is administered by Zhanjiang City. It was called Haikang County before its establishment. It is located in the middle of Leizhou Peninsula, the southernmost part of the Chinese mainland. It faces the South China Sea in the east, Beibu Gulf in the west, Zhanjiang suburbs and Suixi County in the north, and Xuwen County in the south. The total area is 3664.44 square kilometers.

八、关于武山天山的介绍作文?

天山,是一处风景如画的地方。上三年级时,妈妈带我去了一次天山,我至今想起那儿的美景还是记忆犹新。

  那天阳光十分明媚,下了火车,我和妈妈乘着汽车不一会儿就到了天山。一下车,我的眼前顿时开阔起来,那一大片一望无际、嫩绿嫩绿的草地让人不忍心在上面走。草地上成群结队的绵羊正在津津有味地大口大口地吃草。往前走去,是一片松树林。松树密密麻麻地挨在一起,你推我挤,十分有趣。

  往东走几步,是一大片五颜六色、斑驳陆离的花:红的、白的、粉的、黄的……让人看的眼花缭乱。哇!我忽然一抬头,看到了不远处有一面湖,走进一看,它比西湖的水清多了。我站在岸边,湖里各种各样游动的鱼清晰可见。

  天上,那湛蓝湛蓝的天空和洁白如雪的云朵,把天山衬托的更加美丽了。

  啊!天山的风景真是太美了!

九、关于介绍广播的英语作文?

Dear BBC Staff:

I am writing this letter to offer some suggestion.I am a middle-school studentand a ВВC fan.I listen to your programmes nearly every day sO that Ican learn my English well.

No doubt,l likeyour programmes very much,especiallyyour every day news.From my listening,lcan not only study English but also learnsomething new happening in the world.

Here,my suggestion is that,if youcan speak slower,l will be very appreciated.Also,if you can offer somepictures about the news,that will be muchbetter.Meanwhile,l wish that you can haveyour web site so that the audience can bemuch easier to reach you.

十、关于介绍飞机的英语作文?

My First Flight

Last summer, I went to visit my uncle by air. I had never taken a plane before. So I was on top of the world at the news. I was too excited to fall asleep the previous night. On the day of flight, the crew took me from my parents to the seat in the plane. Luckily my seat was near the window. Before the plane took off, I imagined how nice it would be in the sky. But before long I was so tired that I couldn't help sleeping. When I woke up, the plane had just landed. Isn't it interesting?