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Homework Help: Einstein's energy mass relation

  1. Oct 10, 2012 #1
    1. The problem statement, all variables and given/known data
    In Einstein's energy mass relation, the unit for the energy released is Joules, this means that the unit for the mass must be

    a. g
    b. kg
    c. it could be either grams or kilograms
    d. newtons

    2. Relevant equations
    E = mc2

    3. The attempt at a solution
    I believe the answer is B. because kg tend to be the standard for equations I've been working on lately.

    Am I correct??
  2. jcsd
  3. Oct 10, 2012 #2


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    Gold Member

    What is a Joule in SI units?
  4. Oct 10, 2012 #3
    1 J in SI base units is equal to 1 kg·m2/s2.

    The answer was, in fact, B. kg. :smile:
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