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Can C be measured in MeV? If so is this per photon?

  1. Jun 17, 2011 #1
    Can C be measured in MeV?? If so is this per photon?

    Basically as the title states, can you measure C in MeV, i read ALICE was nearing Acceleration of C at 14 MeV (These numbers are what i can remember from a while ago).

    Then is that measure of 14 MeV for say a single atom, or does it apply for larger objects (More mass needs more energy to move it so i think not but i may as well ask)?

    Oh wait, nothing can move at C can it because it hass mass.

    Im starting to think, bad things usually ensue.

    Any help would be great folks. :smile:
  2. jcsd
  3. Jun 17, 2011 #2


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    Re: Can C be measured in MeV?? If so is this per photon?

    No, not really.
    MeV is a unit of energy, with the dimension of joule and c is a speed and has the dimension of meters per second.

    However, the whole point of a particle accelerator is to accelerate particles to high speeds. The reason is that high speeds means high energy (kinetic energy) and this energy can then be used to for example create other particles.

    Hence, if you know the energy of a particle (in for example MeV) and you know its mass you can quite easily calculate its speed.
    This is why particle physicists talk about accelerating particles to a certain energy.

    Also, note that the equations break down if you try to set the speed of a particle to c, this means that there is no energy that corresponds to c.
  4. Jun 17, 2011 #3


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    Re: Can C be measured in MeV?? If so is this per photon?

    You are confusing energy (i.e. the kinetic energy) with speed (c).

  5. Jun 17, 2011 #4
    Re: Can C be measured in MeV?? If so is this per photon?

    So the heavier elements need higher MeV to reach higher acceleration, is this why you cant just keep combining elements like ununoctium to create super heavy elements?
    Im guessing they would be ridiculously unstable anyway but thats for another post i think.
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