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Please help, Express kinetic energy in terms of m and p?

  1. Sep 14, 2005 #1
    Hi, I think my brain froze and i'm not seeing it
    the problem is

    the momentum is defined as
    express the kinetic energy in terms of m and p

    ~ Now I know kinetic = T= (1/2)mv^2
    and that P=mv
    I figured that it must be t= (1/2)p^2
    till i realized that I'm missing in terms of m. I just got stumped
  2. jcsd
  3. Sep 14, 2005 #2
    T= (1/2)p^2

    You know p=mv, so p^2 gives (mv)^2

    T=/= (1/2)(mv)^2

    where =/= represents 'is not equal to'

    I suspect that you will kick yourself when it dawns on you.
  4. Sep 14, 2005 #3
    p=mv -> v=p/m


    T=1/2*m(p/m)^2 -> T=1/2((p^2)/m)
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