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J. Perelman
"Entertaining physics". Book 2.
Chapter 7. Thermal phenomena


"My friends, because we still had Breakfast, " said Michel Ardan his companions on an interplanetary journey. - From the fact that we lost your weight in the gun the projectile, it is not necessary at all that we have lost the appetite. I undertake to give you, my friends, weightless Breakfast, which, no doubt, will consist of the easiest meals ever produced in the world.

And, not waiting for an answer comrades, the French took over the cooking.

Our bottle of water pretending to be empty, " he grumbled to himself Ardan, fumbling with raskupili large bottles. - Do not spend grinding: I know why you are so light... So, the tube is removed. You have to pour into a saucepan its weightless content!

But no matter how much he tilted the bottle, the water was poured.

- Don't work, dear Michel, - came to the rescue Nicole. - Understand that our projectile, where there is no gravity, water can flow. You have to shake out of the bottle, as if gr was thick syrup.

Without hesitation, Ardan slapped on the bottom of the inverted bottle. A new surprise: the neck immediately swollen globe of water, the size of a fist.

What happened to our water? "asked Ardan. - Now, I admit, quite unnecessary surprise! Explain, scientists my friends, what happened here?

- This drop, cute Ardan, a simple water drop. In a world without gravity drops can be anything... Remember that because the liquid only under the influence of gravity to take the form of vessels, pouring in the form of jets, etc. Here there is no gravity, the fluid supplied to its internal molecular forces and should take the form of a ball, as the oil in the famous experience of the Plateau.

- I am nothing to this Plateau with his experiments! I have to boil water for soup, and, I swear, no molecular forces will not stop me! - passionate announced the Frenchman.

He furiously began to shake the water over hovering in the air pot, but, apparently, it was all a conspiracy against peg. Large water balloons, reaching the pan, quickly spreading across its surface. This action did not stop there: with the internal walls of water moving on the exterior, was spread upon him, and soon the pot was wrapped in a thick water layer. Boil water in this form, but there was no way.

- Here's an interesting experience, proving how great is the power clutch, " calmly spoke the furious Ardan calm Nicole. - Do not worry because here the ordinary wetting liquids solids; only in this case, the weight does not interfere with the development of this phenomenon with full force.

And it is a pity that does not interfere! "said Ardan. - Wetting here or anything else, I need to have water inside the pan and not around it. Here's another news what! No chef in the world will not agree to cook the broth under similar conditions!

You can easily prevent wetting, if it bothers you, soothing interposed Mr. Barbicane. - Remember that water does not moisten bodies, covered with at least a thin layer of fat. Obagi its pot outside fat, and you will retain water inside it.

- Bravo! This is what I call true learning, " said Ardan, leading the Board in the execution. Then he proceeded to heat water on the flame of a gas burner.

Positively everything went against Ardan. Gas burner - and she got cranky: Prohorov half a minute dull flame, she went out for some inexplicable reason.

Ardan pottered around the burner, patiently nursed the flame efforts did not lead to anything: the flames refused a handful.

- Barbicane! Nicole! Is there no means to get this stubborn flame to burn as he relies on the laws of your physics statutes gas companies? - cried to friends discouraged Frenchman.

- But there is nothing extraordinary and nothing unexpected, " explained Nicole. Is the flame burns exactly as it should be according to physical laws. And gas company... I think they all went bankrupt would, if it were not for gravity. When burning, you know, form carbon dioxide, water Nar, in a word, non-flammable gases; usually these combustion products but remain near the flame: how warm and therefore more light, they are replaced by inflowing fresh air. But here we have no gravity, so the combustion products remain at the center, surround the flame with a layer of non-combustible gases and block the access of fresh air. Because the flame is so dull here burns and so quickly extinguished. Because the action of fire extinguishers and is based on the fact that the flame is surrounded by non-combustible gas.

- So, according to you, " said the Frenchman, " if the Earth had no gravity, you would not need and fire: the fire went out himself, they suffocate in their own breath?

"Exactly. In the meantime, to help the cause, kindle again the burner and let's blow the flame. We, I hope, will be able to create an artificial cravings and make the flame burn "earthly".

So did they. Ardan then lit the stove and started cooking, not without glee watching, as Nicole with Barbicane alternately blew and was fanning the flames, and to continually fill it with fresh air. Deep down, the Frenchman believed their friends and their science guilty "in all this mess".

- You kind of acting factory pipe, supporting traction - was talking Ardan. "I'm sorry you learned friends, but if we want to have a hot Breakfast, have to obey the dictates of your physics.

However, it took a quarter hour, half hour, hour, and water in a saucepan and never thought to boil.

"You'll have to be patient, darling Ardan. You see, ordinary, significant water heats quickly - why? Just because it is mixing layers: the heated lower layers, lighter, replaced by cold at the top, and as a result all the liquid quickly adopts high temperature. Happened to you ever to heat the water not from below but from above? Then the mixing of the layers does not occur, because the top of the heated layers remain in place. The thermal conductivity of water is negligible, the upper layers can even bring to a boil, while at the bottom will be the pieces still not melted ice. But in our weightless indifferent world, where neither heat the water cycle in the pan can not arise, and the water must be heated very slowly. If you wish to speed up the heating, you must constantly stir the water.

Nicole warned of Ardan, that he did not bring the water to 100°, and limited to a few low temperature. At 100° produces a lot of steam, here with a specific gravity equal to the specific weight of water (both equal to zero), will be mixed with it in a uniform foam.

Unfortunate surprise happened with peas. When Ardan, untied the bag, gently shook him, peas dissipated in the air, and began endlessly wandering around inside the cabin, banging against the wall and Bouncing off them. These floating pea nearly caused a lot of trouble: Nicole accidentally inhaled one of them and so has a fit of coughing, which almost suffocated. To get rid of this danger and make the air clean, our friends began diligently to catch flying pea the net, which Ardan prudently took for collection moonlight butterfly".

It was not easy to cook under such conditions. Ardap was right when he claimed that there was overawed would be the most skilled chef. I had to Tinker a lot and butter with fried steak: I had all the time to hold the meat with a fork, or elastic pair of oil forming under the steak, pushed it out of the pan, and nedodelannoe meat flew "up" - if I may use that word where there was no "top"or "bottom".

Strange picture was presented and the lunch in this world, devoid of gravity. Friends hung in the air in a wide variety of poses, not devoid, however, of picturesqueness, and they repeatedly ran my heads together. To sit, of course, was not necessary. Such things as chairs, sofas, benches is completely useless in a world where there is no gravity. In fact, the table was not needed here, if not for the insistence of Ardan Breakfast would be "at the table".

It was difficult to cook the broth, but even harder was to eat it. To begin with, pour weightless broth cups did not succeed. Ardan little paid for such attempt loss works the whole morning; forgetting that the broth weightless, he angrily struck the inverted bottom of the pan to banish from her stubborn broth. As a result of pots flew a huge spherical drop of the broth in spheroidal form. The Ardan took to show the art of the juggler again to catch and put in the pan so hard cooked broth.

Attempt to use spoons were unsuccessful: the broth to moisten the whole spoon up to the fingers and hung on solid sheets. Covered spoons of oil to prevent wetting, but the point of this is better: the broth turned on spoon into a ball, and there was no way to safely convey this weightless pill to his mouth.

In the end, Nicole found the solution: make a tube of wax paper and using them drank the broth, pulling it into his mouth. In the same way we had our friends while traveling to drink water, wine and all kinds of liquid*.

* Many readers of previous editions of this book appealed to me with letters in which he expressed his bewilderment about how you can drink in an environment without gravity - even by the method specified now: because the air in a flying projectile weightless, therefore, does not produce pressure, and in the absence of pressure not to drink, sucking liquid. In a strange way, the objection is expressed in the media and by some reviewers. Meanwhile, it is obvious that the weightlessness of air under these conditions is not at all related to the absence of pressure: the air pressure in the closed space not because he weighs, but because, as a gaseous body, it tends to expand infinitely. In the open space on the earth's surface the role of the walls, preventing the extension plays severity; this habitual dependence and misled my critics.

Entertaining physics J. Perelman


System Orphus


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