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Some people (who have not studied physics) believe that rockets work because the rocket exhaust pushes against the air, and therefore in the vacuum of space where there is no air, rockets won't work - but that is not the case. Rocket exhaust doesn't need to have air to push against. The expanding gases in the rocket's exhaust nozzle push against the rocket. The gas has its own mass and its own inertia, and the change in momentum of the exhaust gas causes an opposite change in momentum of the rocket. This can be difficult to grasp because we think of gas as being virtually weightless, but a large rocket can emit literally tons of exhaust. The fact that it is in the form of a gas doesn't change the result; mass is mass, whether solid, liquid, or gas.
This is WRONG, rocket DOES work in space.
From NASA
"A rocket is a type of engine that pushes itself forward or upward by producing thrust. Unlike a jet engine, which draws in outside air, a rocket engine uses only the substances carried within it. As a result, a rocket can operate in outer space, where there is almost no air."
How it accelerate
"Rocket engines generate thrust by putting a gas under pressure. The pressure forces the gas out the end of the rocket. The gas escaping the rocket is called exhaust. As it escapes, the exhaust produces thrust according to the laws of motion developed by the English scientist Isaac newton. Newton's third law of motion states that for every action, there is an equal and opposite reaction. Thus, as the rocket pushes the exhaust backward, the exhaust pushes the rocket forward.
The amount of thrust produced by a rocket depends on the momentum of the exhaust -- that is, its total amount of motion. The exhaust's momentum equals its mass (amount of matter) multiplied by the speed at which it exits the rocket. The more momentum the exhaust has, the more thrust the rocket produces. Engineers can therefore increase a rocket's thrust by increasing the mass of exhaust it produces. Alternately, they can increase the thrust by increasing the speed at which the exhaust leaves the rocket."
http://www.nasa.gov/worldbook/index.html
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∙ 14y ago
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Would astronauts on the Moon be able to hear a rocket engine?
I hope so. However, if they see something that would be noisy on the Earth, but in space, like a rocket firing, they would not hear it in space, because sound needs a medium to travel through, like air. There is no air in space, it is mostly a vacuum. So the only sounds an astronaut should hear are his radio, his breathing and anything tapping on his helmet (the air in the helmet will transmit sound waves to his ears).
What does a space suit do for astronauts?
In space, it gives them air to breathe.
Do they wear suits when they go to space because there is no air?
Space suits are worn to protect astronauts not only from the lack of air, but also from cold.
Why did rocket power get canceled?
Because there have been problems with the programing for that show to still air on Nickelodeon. Rocket power was a very awesome show though.
How do spaceships work in space when there is no air to push against?
"Spacecraft use rocket propulsion to move. Rocket engines do not push against air. Off hand I can't think of any engines that push against air. Many engines use air to get the oxygen needed to burn their fuel, but rocket fuel has oxygen in it.If you put a firecracker beside a small block of wood, when the firecracker goes off it will knock the block of wood away from it. Explosions push the things near them away. You can think of a rocket engine like a series of explosions. These explosions push the rocket along.Another analogy is like shooting a shotgun. If you have ever shot a shotgun, you know that it has a lot of "kick." That is, when you shoot the gun it pushes your shoulder back with a great deal of force. That kick is a reaction. If you were wearing roller skates or standing on a skateboard when you shot the gun, then the gun would be acting like a rocket engine and you would react by rolling in the opposite direction".This person has not really understood the question, properly. The reason rocket propulsion allows movement at all is because of Newton's third law of motion; "If body A exerts a force on body B then body B exerts an equal and opposite force on body A".For propulsion, exhaust gases are forced out of the engine and propelled in a direction which is opposite to that of the desired direction of motion. This also pushes the air in that same direction and so air molecules push back on the engine with an equal force, driving it forwards.The problem you have in space is that there is no air and so how can a spacecraft mannouvere itself? The answer is that it pushes off its own exhaust gases which it creates. So I would imagine that there is a momentary period at the begining where the craft will remain stationary until the there are enough exhaust gases to allow propulsion.
How do astronauts change their clothes?
They simply change there clothes! The astronauts don't always have the space suits on! That's only when they actually go into space. When there in a space station or rocket they have air tanks that replenish the air in the rocket and an air pressure controller.
Why only rocket engines can be propelled to space?
Rocket engines are not air breathing engines and hence they can be propelled into space.
Why rocket is used?
A rocket is used for space travel because it requires nothing to push against,no air or ground is needed. The speed and quantity of gas leaving the engine has an equal and opposite force on the rocket propelling it in the opposite direction.
What does a human need to get to outer space?
You, simply, you need a spacesuit and a air tank and a space rocket to get to space
What propells a rocket?
The fuel being ignited by a spark is what propels a rocket to blast off. The mass and the speed are factors as well.
Why will a rocket work in space when there isn't any air?
Rockets in space carry both the fuel and oxidizer with them into space.
What is the difference between a space shuttle and a rocket?
Answer The Space Shuttle is a rocket. By definition, a Rocket is a vehicle that burns gas that it carries with it. Where as, a jet airplane burns the oxygen from the air and is not a rocket. The Rocket when it is launched has a liquid fuel rocket engines at the back end of it. It also has two long, solid fuel rocket engines that separate after launch. But the space shuttle is pulled by a rocket.
How do rockets and space shuttles move in space?
Every action has an equal but opposite reaction. Throw burned fuel very rapidly one way (what a rocket does) and it pushes the rocket the other way. Some people wrongly think a rocket works by pushing the air behind it, but in space there is no air!
Why can a rocket produce more thrust in the vacuum of space than on earth?
Well I'm not sure about an increase in thrust but the reason why it can reach a higher speed is from the lack of air friction.
Why do you need a rocket to go to space?
A rocket is a type of engine that pushes itself forward or upward by producing thrust. Unlike a jet engine, which draws in outside air, a rocket engine uses only the substances carried within it. As a result, a rocket can operate in outer space, where there is almost no air. A rocket can produce more power for its size than any other kind of engine. It can carry people and equipment into space. That is why there is aneed for using rocket to go to spce.
What force sends a rocket to space?
The thrust, which is the force on the rocket due to air. When the fuels are burnt, air (including burnt fuel) is pushed downwards. From Newton's third law, the air exerts an upward force of equal magnitude on the rocket.
Why is a rocket eawier to accelerate as it travels through space?
much less air resistance.
