Internal energy present, is there conservation of energy?

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Discussion Overview

The discussion revolves around the concept of energy conservation, particularly in the context of mechanical energy being converted to internal energy. Participants explore whether energy conservation holds true in such scenarios and the implications of internal energy potentially being negative.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants assert that energy is always conserved, while others suggest that there are exceptions depending on the context.
  • One participant questions whether internal energy can be negative, leading to a discussion about energy being relative to a reference point.
  • There is a mention of energy conservation being applicable in a "closed system," with a clarification that this definition implies energy conservation.
  • A later post introduces a more technical aspect regarding the covariant nature of certain equations, suggesting a potential complexity in the discussion.

Areas of Agreement / Disagreement

Participants express differing views on the universality of energy conservation, with some insisting it always holds and others indicating that exceptions may exist. The discussion remains unresolved regarding the specifics of these exceptions and the implications of negative internal energy.

Contextual Notes

The discussion includes assumptions about the definitions of closed systems and the relativity of energy, which are not fully explored. There are also unresolved mathematical expressions that may influence the understanding of the topic.

makeAwish
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Hmm. This is another thing I'm unsure abt.

When some mechanical energy is converted to internal energy, can we still say that energy is conserved?
Can the internal energy be negative?


Thanks for answering my qns :)
 
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janettaywx said:
When some mechanical energy is converted to internal energy, can we still say that energy is conserved?

You're going to need to be more specific. Yes, energy is always conserved.

janettaywx said:
Can the internal energy be negative?

Energy is always relative to a certain reference, so there's no problem with energy being negative.
 
Energy is always conserved, except when it isn't.

Energy is always conserved in the Classical Physics folder; not always conserved in others. :rolleyes:
 
Energy is always conserved in a "closed system"!


Of course, a "closed system" is defined as one in which energy is conserved!:wink:
 
HallsofIvy said:
Energy is always conserved in a "closed system"!


Of course, a "closed system" is defined as one in which energy is conserved!:wink:

So that's the difference between the folders.

Or is [tex]\partial_\mu p^\nu [/itex] folder covariant?,<br /> <br /> [tex]\frac{d}{df}\partial_\mu p^\nu = 0[/tex][/tex]
 
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