Не се мисли на реакција во смисла на хемиска реакција
Туку на 3 закон на Њутн.[DOUBLEPOST=1456764749][/DOUBLEPOST]Како и да е, да се реши мистеријата прочитајте го овој краток текст
My understanding of space is that it is a vacuum, i.e., devoid of pretty much all matter, just empty space. Also from my amazingly limited knowledge of physics I understand that in order for a force to create movement it must act upon something. So if a spacecraft fires its rockets into space, a vacuum, what is this force is acting upon? If there is nothing there, what are the rockets pushing against to cause the ship to move? Just something I was thinking about because I have way too much free time, your infinite wisdom would be much appreciated.
— Coulter, UCLA
Don't take this personally, Coulter, but you're no rocket scientist.
You're also not the first person who has failed to achieve Zen with Newton's Third Law. Back in the 1920's when Robert Goddard was fathering rocketry, a New York Times editorial dissed him thusly: "That Professor Goddard with his 'chair' in Clark College and the countenancing of the Smithsonian Institution does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react--to say that would be absurd. Of course, he only seems to lack the knowledge ladled out daily in high schools." About what you'd expect from a daily newspaper.
The truth is that the rocket does have something to push against: namely, its own fuel. Let's illustrate with an example you kids can try at home. First, you need to get yourself into some sort of frictionless situation. Wearing ice skates on a slippery ice rink would be good, or maybe your office has a chair that rolls really well on a hard surface. Next, you'll need a medicine ball. You are the rocket and the medicine ball is your fuel. Toss the medicine ball. You'll notice that as you shove the medicine ball forwards, you yourself lurch backwards. Ta-da, the miracle of physics! (If you think this is because the medicine ball pushed on the air, then try the experiment without the medicine ball--just push on the air with your hands, see how far you lurch backwards.)
http://www.straightdope.com/columns/read/1846/how-do-rockets-work-in-the-vacuum-of-space