Can Lagrangian Method be Applied to Solve Rocket Motion Equations?

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Homework Help Overview

The discussion revolves around the application of the Lagrangian method to solve equations related to rocket motion, specifically in a one-dimensional context. The original poster expresses difficulty in obtaining correct results when attempting to apply this method, leading to questions about the underlying assumptions and definitions involved in the problem.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster attempts to apply the Lagrangian method but encounters issues with the resulting equations, suggesting a need to clarify the definitions and assumptions related to rocket motion. Participants raise questions about the meaning of variables, particularly the term "dm," and its implications in the context of the problem.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem. There is a focus on clarifying the definitions of terms and the nature of the motion being analyzed, but no consensus has been reached regarding the application of the Lagrangian method or the correct formulation of the problem.

Contextual Notes

Participants are questioning the assumptions made about the rocket's motion and the nature of the mass being ejected, indicating potential gaps in the original problem statement or setup.

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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