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C = √ (E/m) We can determine c !

  1. Mar 11, 2013 #1
    If this is true why can't we just find an energy divided by a very small mass, square root it and thats what the speed of light equals for that object?
  2. jcsd
  3. Mar 11, 2013 #2
    We can not because [itex] c^{2} [/itex] is the proportionality constant between mass and energy. One can not just find mass and energy in any ratio.
    Last edited: Mar 11, 2013
  4. Mar 11, 2013 #3
    No problem. Just tell us how you would go about accurately measuring the amount of energy in the mass.
  5. Mar 11, 2013 #4


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    Let's have fun with this. Weigh a small mass in a known gravitational field; you've got m. Inject slowly (vanishing KE) into an anti-calorimeter; you've got 2E.

    You can buy anti-calorimeters from the same store that sells 1 light year Born rigid rods, frictionless surfaces, rigid massless shells, etc.
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