Let us review about rocket move

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SUMMARY

The discussion centers on the principles of rocket motion, specifically Newton's Third Law and the conservation of momentum. It establishes that when a rocket expels gas, it moves forward due to the conservation of momentum, despite the apparent loss of mechanical energy. The conversation clarifies that while mechanical energy may not be conserved due to the conversion of chemical energy into mechanical energy, the total energy of the system remains conserved. This distinction is crucial for understanding rocket propulsion mechanics.

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  • Newton's Third Law of Motion
  • Conservation of Momentum
  • Energy Conversion Principles
  • Basic Thermodynamics
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  • Study the principles of rocket propulsion and thrust generation
  • Explore the laws of thermodynamics related to energy conversion
  • Investigate the implications of chemical energy in propulsion systems
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Aerospace engineers, physics students, and anyone interested in the mechanics of rocket propulsion and energy conservation principles.

gema
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Hello Forum,

Let us review about rocket move.The Rocket moving with 2 mechanical principe;Newton's 3 and conservation of momentum.If rocket at t=0 is in rest condition (E=0),after the gas with dm mass go out to the back from rocket ,then rocket move to the front(E=Ek1+Ek2).
Nothing external force in this system,

Energy of system is conserve, if nothing external force in the system.
But why the energy of system isn't conserve?
 
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gema said:
Energy of system is conserve, if nothing external force in the system.
But why the energy of system isn't conserve?
What do you mean by 'energy is conserved'? Just because there are no external forces, doesn't mean mechanical energy (for example) is conserved. You are converting chemical energy into mechanical energy by burning the fuel. (Total energy is conserved of course.)
 

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