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Homework Help: Mass Change Relativity

  1. Apr 13, 2010 #1
    1. The problem statement, all variables and given/known data

    On earth a man weights 78kg. what is his weight on a starship which is travelling at 0.93c?


    2. Relevant equations

    Are the following correct for mass change in terms of relativity?

    mr = E/c2
    m0 = sqrt(E2/c4 - p2/c2)

    Where E is energy, p is momentum and c is the speed of light in vacuum

    Need help solving this!
    Thank you in advance!
     
  2. jcsd
  3. Apr 13, 2010 #2
    Are you sure the problem is stated as weight? Because, if it is, then the solution is pretty simple...

    If it says "mass", then we can do more... :)
     
  4. Apr 14, 2010 #3
    yes it states weight and i think i have an idea of how to do it using the formula
    M= Mo / [√ 1 - v^2/ c^2]
    where Mo is 78kg and velocity is 0.93c
    M= 78 / [√ 1 - (0.93c^2)^2/ c^2]
    M= 78 / [√ 1 - 0.93c^2]
    M=212.2105291kg

    So the weight would be approximately 212.2 kg

    is this correct working and answer?

    thank you in advance~!!!

    s
     
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