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Homework Help: Center mass Kinetic Energy?

  1. Oct 16, 2012 #1
    Wiley Coyote and his Acme rocket, together having inertia of 1000 kg, are speeding after Roadrunner. Upon seeing a large brick wall in his path, Coyote tries to slow down. Unfortunately, he’s still going 5 m/s when he runs into the wall. The wall is not affected, but the rocket crumples (the coyote hangs on), such that the center of mass of the rocket/coyote travels forward 50 cm between striking the wall and coming to rest.

    What is the change in kinetic energy of center of mass of the coyote/rocket combo?

    Would you just use 1/2mv^2?

    I know the center mass velocity equation but that doesnt seem to help. Change in KE would be Initial - Final. Final would be 0 so i just thought that the change in Kinetic would be 1/2mv^2. Is this right?
  2. jcsd
  3. Oct 17, 2012 #2


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    welcome to pf!

    hi pxp004! welcome to pf! :smile:

    (try using the X2 button just above the Reply box :wink:)
    yup! that simple! :biggrin:
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