(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I need to find the maximum distance a rocket (which is actually a bottle filled with compressed air to 654kPa) can travel when the exhuast nozzle is 22cm (and can be changed to any smaller size if needed). Neglect air resistance. The bottles original mass is 50g

2. Relevant equations

Ideal Gas Law: PV = nRT

Bernoullis equation: [tex]\rho[/tex]gh + (1/2)[tex]\rho[/tex]V^2 + P = constant

Thrust Equation: T = m`v

[tex]\rho_{1}[/tex][tex]A_{1}[/tex][tex]V_{1}[/tex]=[tex]rho_{2}A_{2}V_{2}[/tex]=m`

R = [tex]\dot{m}[/tex]v

= [tex]\rho[/tex]AV(v-[tex]v_{0}[/tex]

Density of Air = 1.2062kg/m^3

Pressure of Air = 101.3kPa

3. The attempt at a solution

Well i dont know.

I cant seem to figure out anything here. Bernoulli's equation wont work cause i end up with unknowns on both sides.

m` doesnt make sense. I dont know if i just just sub in a number

veloctity of the gases - i dont know how to find them

im just confused how to do this :x

(ps - i dont want the thing solved. can i just get some help in formulating expressions which can be integrated between 1. Angles of launch and 2. Area of the nozzle)

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# Homework Help: Compressed Air Bottle Rocket (Variable Mass)

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