Can Lagrangian Method be Applied to Solve Rocket Motion Equations?

Abhishek11235
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Homework Statement


While solving equation of rocket motion with Newton's law in 1-d,I pondered to apply Lagrangian method on this. However, I didn't get correct result. Because I can eliminate last 2nd equation using last equation and get some other equation which is certainly not rockets motion.

Homework Equations

The Attempt at a Solution


The attempt is given in screenshot.
 

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Abhishek11235 said:
all variables and given/known data
What is ##dm## ? Dimension ?
 
BvU said:
What is ##dm## ? Dimension ?
A small mass ejected from rocket
 
So you don't describe a rocket but a vessel that throws some object off the ship in a backward direction ?
 

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