- #1
aeroenga
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Homework Statement
okay the problem is there is a two stage rocket with a payload of 200kg and isp 2943m/s. It has a total delta v of 10km/s and at each stage it produces half of the total delta v.
The question is to calculate the initial mass prior to launch, I've been told also that for each stage x, msx which is the structural mass is related to the initial mass mox. (ratio provided as mox/msx = 10)
Also the final mass is defined as the mass of the structure of the second burner (ms2) + payload.
Homework Equations
delta v= cln(m0x/mex) equation (1)
mox/msx = 10 equation (2)
The Attempt at a Solution
started off with final mass me2 = ms2+ 200kg
then i know that from equation two i can write ms2x in terms of mo2x
me2 = 0.1mo2 + 200
then substitute this into equation (1) to find mo2x when making sure delta v = 5000m/s
which i find to be 2414.21kg
now the next stage is that i know mo1 is equal to the mass I am trying to find out and it includes the payload too.
im really confused at what to do from this point onwards, do i just use equation (1) and say that:
m02 is equal to me1 and calculate mo1 from mo1/m02, for delta v = 5000m/s thus finding the total mass prior to launch?