How momentum is related to energy

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Homework Help Overview

The discussion revolves around the relationship between momentum, impulse, and kinetic energy, exploring how these concepts interrelate mathematically.

Discussion Character

  • Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants present equations for momentum and kinetic energy, attempting to derive a relationship between them. Some express concern about eliminating variables and the implications of doing so, particularly in the context of elastic collisions.

Discussion Status

There is a mix of agreement on the mathematical derivation presented, but also a recognition of potential issues with variable elimination. Participants are exploring whether other relationships exist between energy and momentum.

Contextual Notes

Some participants note that relating energy and momentum may be more straightforward in specific scenarios, such as elastic collisions, where kinetic energy is conserved.

UrbanXrisis
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What is the relationship between momentum/Impulse and energy?

Momentum=p=m*v
Impulse=I=F*t
KE=.5mv^2

so...
KE=.5m(p/m)^2
KE=.5*p*(p/m)
KE=p^2/2m
correct?
 
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UrbanXrisis said:
What is the relationship between momentum/Impulse and energy?

Momentum=p=m*v
Impulse=I=F*t
KE=.5mv^2

so...
KE=.5m(p/m)^2
KE=.5*p*(p/m)
KE=p^2/2m
correct?

Yup. Looks good to me.
 
In this case you elimanate the varible v, although you could ralate momentum and energy this way, but the elimanation of the varible v causes lurking varibles. So its best to only relate energy and momentum when you have an elastic collusion, or Kinetic Energy is conserved
 
is there any other relationships between energy and momentum?
 

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