E=mc² Explained: Uses for Projectiles & Explosions

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Discussion Overview

The discussion revolves around the application of the equation E=mc² in the context of projectiles and explosions, particularly in relation to destructive power and asteroid impacts. Participants explore the theoretical implications and practical applications of mass-energy equivalence in these scenarios.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant inquires about the correlation between E=mc² and the destructive power of projectiles and explosions.
  • Another participant asserts that E=mc² is not directly related to projectiles, as they do not convert mass into energy, but acknowledges its relevance in nuclear explosions where a small fraction of mass is converted to energy.
  • A different participant notes that E=mc² is not the sole principle behind atomic weaponry, suggesting that it aided in the development of atomic bombs but is not the only factor involved.
  • One participant expresses confusion about how E=mc² relates to the destruction caused by an asteroid impact, indicating that they were told it is used to measure such destruction.
  • Another participant clarifies that E=mc² is not used to measure the destructive power of an asteroid, suggesting that the kinetic energy formula (E=1/2mv²) would be more appropriate for such calculations.
  • Concerns are raised about the difficulty of converting mass to energy in the context of asteroid impacts, emphasizing that simply colliding an asteroid with a planet does not result in mass-energy conversion.
  • One participant provides a specific example from the Little Boy atomic bomb, noting that only a small amount of mass was converted to energy, leading to a significant energy release.

Areas of Agreement / Disagreement

Participants express differing views on the applicability of E=mc² to projectiles and asteroid impacts. There is no consensus on how E=mc² relates to destructive power, with some arguing it is relevant in nuclear contexts while others assert it does not apply to asteroid impacts.

Contextual Notes

Participants highlight the limitations of applying E=mc² to scenarios involving projectiles and asteroid impacts, indicating a need for clarity on definitions and the specific contexts in which mass-energy conversion occurs.

nicholas0211510
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I know the basics of E=mc² and it being mass energy, but someone told me its also used for projectiles and explosions how does it corrolate with destructive power ?

Thank you in advanced
 
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If you know what "[itex]E= mc^2[/itex]" means then you should be able to work that out. It does not really have anything to do with "projectiles" since that does not change mass into energy. In a nuclear explosion some mass (typically a tiny fraction of the total mass) is converted to energy. Now what that is in "destructive energy" depends on exactly what you mean by "destructive energy". Not all of that energy "destroys" things.
 
Ah that claifys things, and sorry I didn't specify what I ment in destruction, our convo was talking about a astroid striking earth, he said E=mc² is what is used used to measure it , it sounded suspicious so I came here to ask some more experienced people
 
nicholas0211510 said:
Ah that claifys things, and sorry I didn't specify what I ment in destruction, our convo was talking about a astroid striking earth, he said E=mc² is what is used used to measure it , it sounded suspicious so I came here to ask some more experienced people
I'm not sure how that works. Sorry.
 
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Isaac0427 said:
I'm not sure how that works. Sorry.
alright, I guess I'll just do some reading on line

Appreciate the help
 
nicholas0211510 said:
Ah that claifys things, and sorry I didn't specify what I ment in destruction, our convo was talking about a astroid striking earth, he said E=mc² is what is used used to measure it , it sounded suspicious so I came here to ask some more experienced people
E=mc2 is not what is used to measure the destructive power of an asteroid striking earth. The fellow who said it was... was mistaken.

If one wanted to determine the energy released in an impact with such an asteroid, E=1/2mv2 would be the appropriate measure.
 
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The problem is the difficulty of converting mass to energy. Simply colliding an asteroid into a planet isn't going to do it. As others have said, that's not the right kind of interaction.

In an atomic explosion some of the mass is converted to energy. Google found references that suggest for the Little Boy bomb only about 600mg of 64kg was turned into energy. That's a very low percentage of the total mass but a heck of a lot of energy.
 

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