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Rocket Conservation of Moment

  • Thread starter VVS
  • Start date
  • #1
VVS
91
0
Hi,

I really need clarification for this problem.

Homework Statement



A rocket with initial mass M0 is accelerated by expulsion of a partial mass dm of its mass m with a constant velocity u. Write down the differential equation corresponding to the conservation law of momentum for the velocity v(m) of the rocket and evaluate it under the condition v(m = M0) = v0. What is the terminal velocity when the final mass of the rocket is Me?

The Attempt at a Solution



I have attached three different approaches (all using the conservation of momentum principle) of mine in this pdf file.
But unfortunately I get three different results.
Please point out which approach is wrong.

thanks a lot
VVS
 

Attachments

Answers and Replies

  • #2
verty
Homework Helper
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What are your thoughts about the three methods? I think you can apply some physics insight to decide which is correct.
 
  • #3
VVS
91
0
I really can't tell. All three methods appear to be correct to me. I can't see what is wrong about any of the methods. But obviously because I get different answers something has to be incorrect, but I just can't tell what.
 

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