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Why relativistic momentum equals the following?

  • Thread starter Foruer
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  • #1
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In a solution to a problem we were given, it is written that a positron momentum with energy of 2mc2
(where γ=2) is √(γ2-1)*mc = √(4-1)*mc = √3*mc

How did they get that P=√(γ2-1)*mc?
 
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Answers and Replies

  • #2
Nathanael
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You are familiar with p = ϒmv right?
And also with ϒ = 1/√(1-(v/c)2) right?

Eliminate v from the two equations and what do you get?
 
  • #3
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What I get is the answer ?:) thank you :wink:
 
  • #4
Orodruin
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While it gives you the right answer, it is much simpler to use the energy-momentum relation ##E^2 - p^2 c^2 = m^2 c^4## and just solve for ##p##.
 

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