What would be the outcome and what speeds would be needed to create a reaction?
We're going to need a little more information. What reaction are you trying to achieve? What does the plasma consist of?
Say it is Hydrogen Plasma could that be collided into other H and He atom to create propulsion?
Are you talking about nuclear fusion?
Can you answer the question?
Not until I know what you're even asking about.
It appears you are interested in colliding light nuclei together to power space propulsion. The only way I know to achieve that is through nuclear fusion.
Now, do you know anything at all about nuclear fusion? If so, then we have somewhere to start. If not, then I'm going to have to link a few things to explain what it is.
I don't know much about Fusion.
Could H and He be converted into plasma state and collided with other H and He particles within a cubic metre to produce propulsion? What Speeds are needed to create the collision and temperature to create a plasma state.
Yes. This is called nuclear fusion. Which is what I'm trying to tell you about.
I cannot simply answer your question because you don't appear to know how nuclear fusion is done. Speed is irrelevant. There is a spread of velocities for both ions and electrons in a hot plasma. What we care about is the temperature of the plasma. Also, helium isn't likely to be a fuel source for various reasons.
Currently, the primary fuel consists of tritium and deuterium, both isotopes of hydrogen. These isotopes are used because they are the easiest to fuse together and release a great deal of energy. While the reaction rate reaches its peak at about 800 million k, fusion still occurs at much lower temperatures. Because of quantum tunneling, there is no cutoff temperature where fusion no longer occurs. It's just that at low temperatures the chances of two ions fusing together are astronomically small.
For applications specific to space propulsion, see the following:
Would colliding H into each other create energy? If one form was a plasma and the other gaseous.
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