Why is this wrong THRUST? i showed work!

  • Thread starter zcabral
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  • #1
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why is this wrong...THRUST?? i showed work!

Homework Statement



A rocket for use in deep space is to have the capability of boosting a total load (payload plus the rocket frame and engine) of 2.25 metric tons to a speed of 10 000 m/s.
If a different fuel and engine design could give an exhaust speed of 4600 m/s, what amount of fuel and oxidizer would be required for the same task?
metric tons

Homework Equations



vf=ve ln(mi/mf)

The Attempt at a Solution



10000=4600ln(x/2.25)
x= 19.71
but its wrong. can you help?
 

Answers and Replies

  • #2
D H
Staff Emeritus
Science Advisor
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The question asks for the amount of fuel and oxidizer, not the total mass of the vehicle.
 

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