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Homework Help: Particle physics problem

  1. Jan 18, 2012 #1
    1. The problem statement, all variables and given/known data
    A relativistic particle travels a length of 3*10^-3 m before decaying.The decay process of this particle is dominated by.....

    (a)Strong interactions
    (b)EM interactions
    (c)weak interactions
    (d)gravitational interactions.

    2. Relevant equations


    3. The attempt at a solution

    Since the question says the particle is relativistic, i took its velocity = c
    then,
    t = x/v = 10-11
    which is the timescale for weak interactions.

    But the text says the answer is strong interaction.
    Then wheres the mistake?
     
  2. jcsd
  3. Jan 18, 2012 #2

    vela

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    Did you take into account time dilation?
     
  4. Jan 25, 2012 #3
    How can i apply time dilation when velocity is not given?
     
  5. Jan 25, 2012 #4

    vela

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    Good question. Depending on how close to the speed of light the particle travels at, the 10-11 seconds in the lab frame could correspond to an arbitrarily short time interval in the particle's rest frame. I think you need more information to solve the problem.
     
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