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Homework Help: Kinetic Energy

  1. May 27, 2008 #1
    1. The problem statement, all variables and given/known data

    What is the Kineti energy of a 1g (0.001kg) meteor traveling at 30,000m/s? Express your answer in Joules.

    2. Relevant equations
    KE=1/2MV^2


    3. The attempt at a solution
    1/2(.001kg)(30,000)^2 = 450000J


    Now since 30,000 is squared, would i have to multiply .001kg by 4, before i did all of this math?
     
  2. jcsd
  3. May 27, 2008 #2
    Nope. You just plug .001kg in for M. Out of curiosity, why would you multiply by 4?
     
  4. May 27, 2008 #3
    I thought that since v is squared, you had to multiply the mass by 4.......or is that only if its 2v^2?
     
  5. May 27, 2008 #4
    Nope, the one half is a separate term from the squared term:

    KE = (1/2) * (m) * (v2)
     
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