Calculating Energy of Separating Stars: Potential vs Kinetic Energy

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Discussion Overview

The discussion revolves around the calculation of energy required to separate two stars to an infinite distance, focusing on the roles of potential and kinetic energy in this context. It involves theoretical considerations of energy states in astrophysical systems.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions the necessity of including kinetic energy in the calculations for separating the stars, suggesting a hypothetical scenario where kinetic energy remains unchanged after separation.
  • Another participant asserts that the work needed to separate the stars to infinity corresponds to the potential energy of the system in its initial state, emphasizing that total energy includes both potential and kinetic energy.
  • A later reply confirms the assignment's explicit request for the energy needed to separate the stars to an infinite distance, indicating a focus on the problem's wording.

Areas of Agreement / Disagreement

Participants express differing views on the inclusion of kinetic energy in the calculations, indicating that multiple competing perspectives remain unresolved.

Contextual Notes

Participants reference the wording of the assignment, which may imply specific assumptions about energy states that are not fully explored in the discussion.

zezima1
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I recently did an exercise where I had to calculate the total energy needed to separate the stars completely from each other - i.e. make the distance between them infinity.
One then had to calculate the potential energy between them as well as their kinetic energies. But there's something I don't get here - why do you have to use the kinetic energy in the calculations too. Couldnt you imagine a situation where the kinetic energy was the same after they had been separated by a distance of infinity.
 
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Work needed to separate the stars to infinity is the potential energy of the system in it's initial state. The total energy of the system is the potential energy and the kinetic energy.

Check the wording of the problem.
 
Well the assignment explicitly asks: What amount of energy is needed to separate the stars to a distance infinitely far from each other.
 
Well then, I'd say you have a point :)
 

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