The third is the most elaborated, but is not finished.
What is the rocket equation? Basically it say that with
a given quantity and type of a propellant/oxydiser your rocket will
accelerate till there is no more fuel to burn.
After that the rocket speed stay at this last speed until it encounter something large and heavy!
Final speed = ISP*log(Empty
What is ISP : ISP is the time to burn an unit of mass of propellant/oxidizer.
It's often the subject of boring threads on my favorite News Group.
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