Rocket Science and Newton...

[YT2095]

I`v been considering one of Newtons laws in relation to Rocket science, specifically Water rockets and was wondering if I would get more thrust if the water being thrown out the back was heavier, such as a saturated salt soln.

 

but then I figured that the rocket and the water it was carrying would Also weigh more and thus it would cancel out any advantage it may give me.

 

so I went to opposite extreme and thought why does it need it water at all? can`t I just use the air alone.

but then I figured that would work only if the bottle itself weighed nothing.

 

so somewhere in between Must be an optimum "fuel" density, does anyone know what that would be for using a 2l plastic soda bottle with a mass of 44 grams empty?

[insane_alien]

air alone would work, just not effectively as it is so light.

 

one way to increase the thrust is a higher pressure inside, this would also increase momentum.

 

i'll do some math later and i'll see how the increased mass affects it. i'll also see if an optimum can be worked out.

 

actually, found this site it'll calculate it for you http://polyplex.org/rockets/simulation/

[YT2095]

Fantastic thanks!

 

it seems a lower density (to a point) is way to go.