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I Need a practical example of E=mc^2 with real numbers

  1. May 29, 2018 #1
    Need a practical example of E=MC2 with real numbers

    Ok, so I understand that Energy = Mass of an Object * Speed of light square, if we must convert this to numbers, how can this be presented for let’s say 1,000 hydrogen atoms?

    Energy = 1.008 (Hydrogen mass) * 1,000 (hydrogen atoms) * speed of light * speed of light
    Energy = 1.008 * 1,000 * 299 792 458 m / s * 299 792 458 m / s

    The first 2 parts are ok, but what about the speed of light, that is miles per second, is there a number there that removed the m/s so we can calculate it?

    And what about E, what kind of units result in E?
  2. jcsd
  3. May 29, 2018 #2


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    Energy in SI units is Joules (J). 1 J = 1 kg⋅m2/s2. Your formula is incorrect because you did not express the mass of the hydrogen atom in kg. You need to look that up. Note that in your formula so far you have the m2/s2. BTW m in m/s stands for "meters" not miles. Miles per second is sometimes written as mi/s or spelled out entirely to avoid confusion.
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