Question about momentum and kinetic energy

AI Thread Summary
Kinetic energy is defined as half the mass multiplied by the square of velocity, while momentum is the product of mass and velocity. The discussion highlights that the conservation of kinetic energy relates to time symmetry, whereas momentum conservation is tied to spatial symmetry. Participants suggest exploring Noether's theorem for a deeper understanding of these concepts. There is a request for intuitive explanations regarding the relationship between velocity squared and symmetry. The conversation emphasizes the importance of these principles in physics.
larsa
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First of all i am not a native speaker so i apologize for my english.
Kinetic energy is velocity squared multiplied by mass, whereas momentum is just velocity multiplied by mass.
I have read that the reason for this is because conservation of kinetic energy is related to symmetry of the motion in time and conservation of momentum is related to the symmetry in the motion of space.
Could someone give an intuitive or not explanation about this?

Thank you in advance
 
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Do a search on Noether's theorem on PF. You will find many thread discussing the subject.
 
DrClaude said:
Do a search on Noether's theorem on PF. You will find many thread discussing the subject.
What i don't understand is how velocity squared is related to symmetry. I have not found any explanation about this. I will look again, thanks
 
larsa said:
First of all i am not a native speaker so i apologize for my english.
Kinetic energy is velocity squared multiplied by mass, whereas momentum is just velocity multiplied by mass.
I have read that the reason for this is because conservation of kinetic energy is related to symmetry of the motion in time and conservation of momentum is related to the symmetry in the motion of space.
Could someone give an intuitive or not explanation about this?

Thank you in advance

There is no need to apologise for your near perfect English!
 

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