橡皮筋能打开西瓜,这是真的吗?橘子皮能引爆气球,这是真的吗?纸能托起比自己还要重的东西,这是真的吗?今天,我们为了解决第三个问题,就做了这个实验——用纸托起重物。
作文课上,姚老师说:“我们今天来做一个实验,那就是用一张很薄的A4纸,去托起一些重物。”我们一听这个消息,十分激动,看来,今天又要来一次科学之旅了。
同学们有的若有所思,有的眉头紧锁,有的七嘴八舌地讨论着。讨论一会后,大家都胸有成竹。
姚老师清了清嗓子,大声说:“规则是这样的,在托东西的时候,不可以用手接触纸,只可以让纸去托起,开起你们智慧的小脑袋瓜子吧!我要看一看谁的.纸能托起更重更多的东西吧。”
当老师说完话后,全班都不敢相信。我心想:“这个题目说难,其实又不难,说简单,其实并不简单。这个题目,是否有独门秘籍?”
当老师发下了纸,我们开始动手了。不过几分钟,刘子骞就用双手提着纸交出了答案,纸上放有很多的书。老师一看忙说:“不对,不能用手托着。”我们一听,十分惊讶。
汪汉林第二个提交答案。他折了一个很大的三角形,可是站不稳,书本一放上去立马就被压倒掉了。接着,他又做了一个正方形,我想:正方形不具有稳定性。答案与我想像的一样,书刚放上去“轰隆”一声倒了。
对手的失败启发了我的思考,我做了一个多三角形的塔,将物体一个又一个放上去,可惜放到第六个,我的多三角形塔就倒了。我又把三角形加大密度,最后成功了,我的多三角形塔一共放了28个物体,三角形的纸还是纹丝不动。我十分开心。老师说:“三角形具有稳定性,在多三角形很密的时候,稳定性更大了,所以能放许多东西。”
在生活中,有许多东西有三角形,房顶是三角形、衣架是三角形、围篮是三角形……真是数不胜数。
这个实验让我懂了,做事要通过缜密的思考,反复尝试,这样才可能获得成功。
to prevent H7N9 we should know some common sense. First of all, it is important for us to prevent H7N9 from ourselves. For example, clean our hands frequently.
Sencondly, do more exercises. Such as running. Lastly, change our diet to keep balence. For example, eat more types of vegetables and drink more water
有一天,小王对张明说:“快给我一张草稿纸,我急着用。谢谢了!”就这样,我被张明顺手递到了小王的手中。小王接过我后就在我的身上乱涂乱画,还把我划破了呢!他不仅把我搞得破烂不堪,还把我随手扔在了地上……
晚上,环卫工人将我扫起,倒入了垃圾车里。垃圾车里又脏又臭,简直不能呼吸了。让我没想到的是,我看到了一位老朋友,铅笔哥哥。铅笔哥哥问我:“你怎么也来了?”我说:“说来话长啊!我们公司里的`一位员工叫小王,他把我拿走了。起初我以为我在办公桌上待了那么多天,终于可以为人类干点事了。可是让我没有想到的是,小王根本就在浪费我,他在我的身上乱涂乱画……算了,不说了,铅笔哥哥你又经历了怎样的事呢?”铅笔哥哥说:“我的遭遇也比你好不到哪里去。公司里的人开始对我特别的好,你也知道我们铅笔的寿命很短。慢慢地我变短了,他们也开始嫌弃我了。就被他们扔进了垃圾车里。其实你不说,我看你这遍体鳞伤的样子我就知道你受的苦不比我少……”
突然车子一阵颠簸,我被颠到了马路上。不过幸运的是,一位戴着红领巾的少先队员把我捡了起来,并把我送进了回收站里,经过人类的重新加工,我又变成了别的样子,重新为人类工作……
人类啊!你们知道吗?我们原本是一棵大树,你们知道小树长成参天的树要多少年的时间吗?至少要十几年。为了更好地为你们人类服务,我们被砍伐并经历了各种痛苦才变成了一张纸,虽然一张纸算不了什么,但是一百张、一千张、一万张呢?那可是一大片森林啊!快点行动起来吧!爱惜我们吧!
How to prevent the H7N9?
As is well known,the A flu is spreading throught our country. However, if we negnect it, the deadly H7N9 may cause more infectors,or even more deaths. So what is the most important is that we should take some effective measures to prevent it.They can be listed as follows.
Firstly,it is necessary for you to realize the Avian flu can be prevented if you develop good living habits. For example,you shouldn’t forget to wash your hands before meals.Besides,don’t spit everywhere and try to cover your mouth or nose with paper or hankerchiefs when you have to cough or sneeze.What’s more, remember to wear the mouth-cover if you have to go to the public places, such as the crowded cinemas,supermarkets, buses,where the A flu may spread easily.
Secondly,of course, taking exercise more often and taking good sleep to build your body are wise choices for you to reduce the risk of being infected.
Last but not the least, if you are unlucky to be infected with the slight flu cold, try to stay at home,and take some medicine. Do pay attention to your daily body temperature. If you have a high fever, go to the hospital without delay for further treatment. Make sure you are not expected to come back to school before the cold or flu is cured.
Only by doing like this can you prevent or defeat the A flu in the end.
Expert tips on how to prevent avian influenza H7N9 collated by current argument data dictionary
1.平时加强体育锻炼,多休息,避免过度劳累,不吸烟,勤洗手;注意个人卫生,打喷嚏或咳嗽时掩住口鼻。
1 usually strengthen physical exercise, rest more, avoid excessive overworked, do not smoke, wash their hands; pay attention to personal hygiene, when sneezing or coughing and cover your nose and mouth.
2.保持室内清洁,使用消毒液清洗的地毯,避免使用难以清洗的地毯,保持地面、天花板、家具及墙壁清洁,确保排水道通畅;保持室内空气流通,应每天开窗换气两次,每次至少10分钟,或使用抽气扇保持空气流通;尽量少去 空气不流通的场所。
2 keep the room clean, use disinfectant cleaning carpets, avoid the use of hard to clean the carpet, keep the floor, ceiling, furniture and walls clean, to ensure smooth drainage channel; maintains the indoor air circulation, ventilation windows should be at least two times a day, 10 minutes each time, or use a fan to keep air circulation; as little as possible to airless places.
3.注意饮食卫生,进食禽肉、蛋类要彻底煮熟,加工、保存食物时要注意生、熟分开;养成良好的卫生习惯,搞好厨房卫生,不生食禽肉和内脏。解剖活(死家禽、家畜及其制品后要彻底洗手。
3, pay attention to food hygiene, eating meat, eggs should be thoroughly cooked, processing, preservation of food to the attention of raw, cooked separately; develop good health habits, good kitchen hygiene, do not eat raw poultry meat and offal. Anatomy of living (dead to wash hands thoroughly, livestock and poultry products.
同时,在户外洗手不方便的时候,可以使用免洗洗手液,随身携带,随时随地隔离病菌,呵护您的健康。
At the same time, when the outdoor hand-washing is not convenient, can use hand sanitizer, carry whenever and wherever possible, isolate the pathogen, take care of your health.
4.发现疫情时,应尽量避免与禽类接触;公众特别是儿童应避免密切接触家禽和野禽。
4 found in the epidemic, should avoid contact with poultry; the public especially children should avoid close contact with poultry and wild birds.
5.注意生活用具的消毒处理。禽流感病毒不耐热,100°C下一分钟即可灭活。对干燥、紫外线照射、汞、氯等常用消毒药都很敏感。
5 pay attention to disinfection and living appliances. Avian influenza viruses do not heat, 100 ° C, one minute can be inact
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