Can Negative Mass be Plugged into Conservation of Momentum and Energy Equations?

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Discussion Overview

The discussion revolves around the application of negative mass in conservation of momentum and energy equations, particularly in the context of elastic collisions. Participants explore theoretical implications and mathematical outcomes of using negative mass in these equations.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant describes a scenario involving a -1kg ball colliding with a 2kg ball, noting different outcomes for the speed of the positive ball depending on the mass of the second ball.
  • Another participant argues that applying mathematics to a non-real problem may yield results that lack meaning in the real world, emphasizing the importance of context in mathematical applications.
  • A different participant claims there is a proof that Newtonian mechanics can accommodate negative masses, referencing a Wikipedia page as a source.
  • Another participant suggests that experimentation would be the best way to investigate negative mass, but notes the lack of practical examples in Newtonian mechanics and the unusual predictions associated with negative mass in other physics areas.

Areas of Agreement / Disagreement

Participants express differing views on the validity and implications of negative mass in physics. There is no consensus on whether negative mass can be meaningfully integrated into conservation laws or if it leads to valid physical interpretations.

Contextual Notes

Some limitations include the speculative nature of negative mass, potential dependencies on definitions, and the unresolved status of mathematical steps in the application of negative mass to classical mechanics.

pantheid
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I'm trying to plug in negative mass into conservation of momentum and energy equations. I want to see what would happen if a -1kg ball traveling at 1m/s smacks into a 2kg ball in an elastic collision. If the second ball is 1kg, then it remains stationary while the negative ball continues to travel at 1m/s, like they didn't even interact. If its 2kg, I get 2 answers for the speed of the positive ball, zero and negative two. How do I know which is correct?
 
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If you try to apply Maths to a non real problem then you will not get an answer that has no meaning in the real world. Your Maths will give you a correct Mathematical answer if you make all the steps correctly but, as with Computers, GIGO.
 
I believe there is a proof that Newtonian mechanics hold for negative masses. It can be found on the wikipedia page for negative mass, so technically its not garbage.
 
The best way to find out is with an experiment, but that is not an option. I have never heard of negative mass being used in Newtonian Mechanics, and most of the time when negative mass comes up in other areas of physics, it predicts things that have never been observed. That doesn't mean that it doesn't exist, but you might be better off researching different topics.
 

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