How momentum is related to energy

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Momentum and energy are interconnected through the equations for kinetic energy (KE) and momentum (p). The relationship can be expressed as KE = p^2 / (2m), which shows how momentum can be used to derive kinetic energy. While eliminating the variable velocity (v) can simplify the relationship, it may introduce complexities in understanding the dynamics involved. It is emphasized that these relationships are most straightforward in elastic collisions, where kinetic energy is conserved. Overall, momentum and energy can be effectively related, particularly in specific conditions like elastic collisions.
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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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