One of the most amazing missions that man has ever undertook was to space exploration, of astonishing complexity. Space exploration is complicated because there are many problems to solve and obstacles to overcome-things like:
- the vacuum of space;
- problems with heat management;
- the difficulty of re-entry;
- orbital mechanics;
- micrometeoroids and space debris;
- solar and cosmic radiation;
- the logistics of how to have a bathroom in a gravity-free environment.\
But the biggest problem of all is to get enough energy to just get the aircraft off the ground. That’s where rocket engines.
Rocket engines are, on the one hand, so simple that you could assemble and fly on its own rocket model without spending a lot (see links on the last page of the article for more details). On the other hand, rocket engines and fuel systems are so complicated that only 3 countries managed to put people in orbit. In this article, we’ll take a look at the rockets ‘ engines to understand how they work, as well as to understand some of the complexity that surrounds them.
When most people think about engines, remember. For example, the gasoline engine of a car produces rotational energy to move the wheels. An electric motor produces rotational energy to rotate a ventilator or rotate a disk. A steam engine is used to do the same thing that makes a steam turbine and the majority of gas turbines.
Rocket engines are radically different, as are the reaction. The basic principle on which is based on the engine of a rocket is the famous Newtonian principle according to which “every action a reaction of equal intensity and anticlockwise”. A rocket engine is playing for a mass sense and benefiting from the reaction that occurs in the opposite direction as a result.
This concept of “play dough and benefit from the reaction” can be hard to take in at first because that’s not what seems to be happening. See the following examples to get a better idea of the reality.
If you’ve ever shot with a shotgun, especially a large 12 gauge, then you know that the “Kickback” is pretty strong. This Kickback is a reaction. A shotgun shoot about 30 grams of metal in a direction approximately 1100 km/h, and your shoulder feels the impact of the reaction. If you were using skates or a skateboard to shoot with the gun, she would be acting as a rocket engine and you would react by rolling in the opposite direction.
If you have ever had the opportunity to view a fire hose of these large playing water, may have noticed that it is necessary to use a lot of force to hold the hose (sometimes 2 or 3 firefighters are required). The hose is acting as a rocket engine. She is throwing water in one direction and the Fire Department is using his strength and weight to counteract the reaction. If they release the hose, she would be hitting all around with tremendous force. If firefighters were on skateboards, the hose would push them backwards at great speed.
When you fill a balloon and let her fly across the room, is designing a rocket engine. In this case, what is being played are air molecules that are inside the bladder. Many people believe that the air molecules do not weigh anything, but they have weight (see the page on helium to get a better sense of the weight of the air). When they come out through the mouth, the rest of the bladder reacts in the opposite direction.
Action and reaction:
Imagine the following situation: you’re wearing a space suit, is floating in space next to the space shuttle and has a baseball in his hand.
If you throw the baseball, your body will react by going to the opposite side of the ball. What controls the rate at which your body turns away is the weight of the ball that you throw and the amount of acceleration applied to it. The mass multiplied by acceleration is equal to the force (f = m * a). Whatever the force applied to baseball, it will be equalized by an identical reaction force applied to your body (m * = m * a). So, lets say the ball has 0.5 kg and its body and the space suit together have 50 kg. You throw the ball at a speed of approximately 10 m/s (36 km/h). That means you speed up to 0.5 kg of baseball with his arm for her to win a speed of 36 km/h, your body reacts, but he has 100 times more mass than the ball. Therefore, he departs the 100th the speed of baseball or 0.1 m/s (0.36 km/h).
If you want to generate more thrust to his baseball, has 2 options: increase the weight or increase the acceleration. You can throw a ball heavier, shooting several balls one after the other (increasing mass) or throw the ball faster (increasing its acceleration). But that’s all you can do.