How much fuel is needed to reach a specific velocity in rocket propulsion?

AI Thread Summary
The discussion revolves around calculating the fuel required for a rocket to achieve a specific velocity, focusing on the space shuttle's parameters. The shuttle has an initial mass of 2.41 million kg and reaches an initial velocity of 4632 m/s, needing to attain a final velocity of 5158 m/s. The user initially struggled with the equations related to thrust and acceleration, particularly how to derive dv/dt. After some calculations and adjustments, they found that the amount of fuel needed to reach the desired velocity is approximately 5.96×10^4 kg. The conversation highlights the complexities of rocket propulsion calculations and the importance of understanding the underlying physics.
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Homework Statement


The space shuttle, with an initial mass M = 2.41E+6 kg, is launched from the surface of the Earth with an initial net acceleration a = 26.1 m/s2. The rate of fuel consumption is R = 6.90E+3 kg/s. The shuttle reaches outer space with a velocity of vo = 4632 m/s, and a mass of Mo = 1.45E+6 kg. How much fuel must be burned after this time to reach a velocity vf = 5158 m/s?
 
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well i got some answer..but all of them were wrong. Ve(dm/dt) = M(dv/dt), Vf-Vi= Ve(ln(Mi/Mf)...As it reaches outer space, I got acceleration of 43.38 and since gravity is not acting, added 9.81 to get 53.19. I set this to dv/dt. Got Ve. And plugged into formula...but did not work. What's wrong?
 
My only question is, on equation Ve(dm/dt) = M(dv/dt), how do we get dv/dt? I really don't get it..Is it constant?
 
Oops, I solved the problem! FYI answer is 5.96×10^4 kg.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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