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kinetic energy/momentum conservation (rest mass energy)

Discussion in 'MCAT: Medical College Admissions Test' started by IndyZX, Apr 30, 2004.

  1. IndyZX

    7+ Year Member

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    when an atom shoots off an alpha particle during alpha decay, is kinetic energy or momentum conserved?

    i say neither is conserved, what do you think?
     
  2. liverotcod

    liverotcod Lieutenant Crunch
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    I think it would be:
    kinetic energy: no, because mass is being converted to kinetic energy
    momentum: yes, because the nucleus will recoil in response to the alpha particle ejection.
     
  3. IndyZX

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    doesnt total mass increase? some of the weak nuclear force is coverted to mass i thought...
     
  4. UCLAstudent

    UCLAstudent I'm a luck dragon!
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    Yes, I believe that this is correct.
     
  5. liverotcod

    liverotcod Lieutenant Crunch
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    I'm not 100% clear... but this site is helpful. There is mass lost in alpha decay, probably because of the decrease in potential energy in the parent nucleus after the decay.
     
  6. Nuel

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    Mass is probably lost due to speed of these nuclear particles (dilation factor effect), especially electrons--decrease in potential energy which follows from increase in KE of the moving particles.

    I think I just rambled nonsense here :oops:
     
  7. Shrike

    Shrike Lanius examinatianus
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    Everyone's got the right answer here (KE not conserved, because a massive particle is ejected; momentum conserved). Just wanted to point out: momentum is always conserved, as long as you're considering a closed system.
     
  8. IcedCube

    IcedCube Senior Member
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    mcat knowledge in one ear, out the other.
     

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