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从4月话题的讨论情况来看,同学们的参与热情越来越高了,“灌水乐园”的人气也越来越旺了.全国各地的很多同学寄来了信或者发来了电子邮件,纷纷就这一话题发表自己的看法.尽管这些看法不一定完全正确,但它表明同学们积极为了给同学们提供一个利用实验研究问题的机会,7月话题请同学们一起来探究一下著名的“姆潘巴问题”:据说1963年,坦桑尼亚的中学生姆潘巴经常与同学们一起做冰淇淋吃,他们总是先把生牛奶煮沸,加入糖,等冷却后倒入冰格中放进冰箱的冷冻室内冷冻.因为做冰淇淋的同学很多,所以冷冻室的位置总是比较紧张.有一天,姆潘巴做冰淇淋时,一位同学为了抢在他的前面,竟然把生牛奶放到了冰箱的冷冻室里.姆潘巴只得急急忙忙把牛奶煮沸,放入糖,等不得冷却,就把滚烫的牛奶倒入冰格,放到冰箱的冷冻室里去了.过了一个半小时,姆潘巴发现他的热牛奶已经结成冰,而其他同学的冷牛奶还是很稠的液体,没有冻结！这个问题引起了广泛的争论,有人力图分析其中的奥秘,也有人把它说成愚人节的恶作剧,甚至列为20世纪十大科学骗局之一.请同学们自己做一次对比实验,可以用冷牛奶和热牛奶,也可以用冷水和热水,把它们同时放到冰箱的冷冻室里.在你吃完自制的冰淇淋时,别忘了把实验结果告诉我们,并说一下自己的想法.来信请寄:(45000
Judging from the discussions on the topic in April, the students’ enthusiasm for participation increased, and the popularity of the “Irreverent Garden” became more and more prosperous. Many students from all over the country sent letters or sent e-mails. E-mails have expressed their opinions on this topic. Although these views are not necessarily correct, it shows that the students are actively providing students with an opportunity to use experimental research questions. In July, they asked the students to explore the famous ones together. The “Mpanba issue”: It is said that in 1963, Tanzanian middle school student Mpeba used to cook ice cream together with his classmates. They always boiled raw milk, added sugar, and then poured it into an ice cube after cooling. Into the freezer inside the refrigerator to freeze. Because there are a lot of students to do ice cream, so the location of the freezer is always tense. One day, when Mpamba was making ice cream, one classmate actually put raw milk in front of him. In the freezer of the refrigerator, Mpunba had to hurry to boil the milk and put sugar into it. When it was not allowed to cool, he poured hot milk into the freezer and put it in the freezer of the refrigerator. It took an hour and a half. Mpamba found him Has been hot milk into ice, cold milk and other students is still very thick liquid, not frozen! This issue has caused widespread controversy. There are manpower plans to analyze the mystery, and some people have described it as an April Fool’s Day mischief, even as one of the top 10 scientific scams of the 20th century. Ask students to do a comparative experiment by themselves. Cold milk and hot milk, you can also use cold water and hot water, put them in the freezer of the refrigerator at the same time. When you finish home-made ice cream, do not forget to tell us the results of the experiment, and talk about their own ideas. Letters please send: (45000