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With that said, what should I take into account? Gravity, wind velocity, shape of cone of the rocket, density, anything else? And would temperature be a factor?

The rocket will be made out of a coke bottle (2 L) and it will start with about 300-800 mL of water (I'm not so sure on the amount) so I will have to take into account the change of momentum over time, and we will use 45-60 psi.

This is what I have so far:

For thrust, T = [itex]\frac{\pi}{2}[/itex]PD

^{2}

Height, h = ([itex]\frac{Mi}{Mr}[/itex])

^{2}([itex]\frac{Pi}{\rho g}[/itex]) where Mi is the mass of the water only, Mr is the mass of the rocket when empty, Pi is the initial gauge pressure inside the rocket, and ρ is the air density.

External forces, M[itex]\frac{dv}{dt}[/itex] = [itex]\alpha[/itex]V

_{e}+ F

_{ext}= [itex]\alpha[/itex]V

_{e}+ F

_{g}+ F

_{drag}, where [itex]\alpha[/itex] is -([itex]\frac{dM}{dt}[/itex]), V

_{e}is the velocity of the water leaving nozzle, and is it safe to suggest that F

_{d}is Stokes' drag at small velocities (F

_{d}[itex]\propto[/itex] -b[itex]\upsilon[/itex])?

And I don't know how to account the shape of wings and all that. Any suggestion?

And what else should I add?

In essence, I want to be able to calculate a model that would fly the highest and fastest.