jedishrfu said:At the microscopic level, I think you are right. In general though, it is explained as an application of Newtonian physics via the conservation of momentum where the exhaust from the rocket burn is mass ejected and so the rocket goes forward as a consequence. It you look at it microscopically, a chemical reaction occurs, energy is released, molecules move faster and temperature and pressure builds with some molecules escaping out the nozzle and others pushing against the rocket chamber pushing the rocket forward.
There are other forms of propulsion though as described in the wikipedia article:
http://en.wikipedia.org/wiki/Spacecraft_propulsion
Yes.So then if the propulsion is caused by the molecules of gas with high kinetic energy pushing the inside of the rocket, is it possible while in space to heat the gases inside the rocket and release them to cause further propulsion in space
Simon Bridge said:Yes.
Although just having a high speed (=high temperature) gas is not enough - you also have to let it out.
I take it you are thinking of using solar power to heat the gas?
This will work - and light-propulsion systems working on that principle have been developed.
Note: if you throw anything at all one way, you will move the other way (unless something stops you.)
This is how we'd normally think about how rockets work ... burning the fuel results in hot gasses, the rocket tube only has one exit - so the gasses escape that way very fast. The rocket goes the other way.
Siddharth Menon said:Yes Newtons law, but is this also possible in space where there are no particles present. I am thinking of a concept of an electric propulsion system which would obviously include the concepts of magnetism and such.
Like that physics prof 100 years ago who said that in the New York Times (that rockets in space couldn't work because there would be nothing for them to push against). This is so fundamentally wrong that I didn't think it was what he meant.Bandersnatch said:He's thinking of "molecule collision causing propulsion" but in the sense of molecules of the propellant pushing on the molecules in the air - a common misconception of how rocket propulsion works.
Alright i understand that, so it is possible to change direction etc. using hot gases. It may seem like i am asking stupid questions but i just want to be sure.phinds said:Like that physics prof 100 years ago who said that in the New York Times (that rockets in space couldn't work because there would be nothing for them to push against). This is so fundamentally wrong that I didn't think it was what he meant.
Rocket propulsion is the process of using hot gases to propel a rocket forward. This is achieved by expelling the gases at high speeds through a nozzle, creating a reaction force in the opposite direction, which moves the rocket forward.
The hot gases are created by burning a fuel, such as liquid hydrogen or kerosene, with an oxidizer, such as liquid oxygen. This creates a controlled explosion in the combustion chamber, which produces hot gases at high pressure. The gases are then forced through a nozzle, which accelerates them to even higher speeds, propelling the rocket forward.
The two main types of rocket propulsion are chemical and electric. Chemical propulsion, as described above, uses a chemical reaction to produce hot gases. Electric propulsion, on the other hand, uses electricity to generate a stream of charged particles, which are then accelerated out of the rocket to create thrust.
Rocket propulsion is one of the most efficient forms of propulsion, as it can generate a high amount of thrust with relatively little fuel. However, the efficiency can vary depending on the type of rocket and the specific design of the propulsion system.
One of the main challenges of rocket propulsion is the high amount of energy required to create the hot gases. This means that large amounts of fuel are needed, which can make rockets heavy and difficult to launch. Additionally, rocket engines must be designed to withstand extreme temperatures and pressures, making them complex and expensive to build and maintain.