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Homework Help: Kinetic energy transfer problem

  1. Jan 20, 2005 #1
    ok i have a problem with a 0.005kg coin that has an initial velocity of 25cm/s that hits a 0.015kg coin that is at rest. atfer the collision the 0.005kg coin has a velocity of -12.5cm/s. What i have to find is the Kinetic energy transferred was. i got the final velocity for the 0.015kg coin which is 12.5cm/s but i don't know how to figure out the amt of kinetic enegy transfer is can someone plz help!
     
  2. jcsd
  3. Jan 20, 2005 #2
    Transferred kinetic energy is that which is gained by the coin that was initially at rest. Therefore, you can use

    [tex]E_{K}=\frac{1}{2}mv^2[/tex]

    to find the final kinetic energy of that coin, which, since initial [itex]E_{K}=0[/itex], is the transferred [itex]E_{K}[/itex].
     
    Last edited: Jan 20, 2005
  4. Jan 20, 2005 #3
    but when i do that i get 1.172 for an answer but it says in my book that the answer is 1.1x10^-4J???
     
  5. Jan 20, 2005 #4
    Take a look at your units...
     
  6. Jul 9, 2010 #5
    I have an 8lb sledge hammer, traveling 50 mph hitting an immovable object. The energy created is Ek = 1/2 mv^2. Is the energy transfer to the immovable object the same amount?
     
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