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Energy Equvalant of different masses

  1. Mar 30, 2013 #1
    I'm trying to learn here. After all, you all know more about this stuff then I do. If you were to take a given mass of uranium and compare it to say, a mass of butter having the same number of electrons, do they both contain the same amount of energy if it could be released like in a bomb? I know it can't be released in the butter.
  2. jcsd
  3. Mar 31, 2013 #2


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    Mass and energy are equivalent, but are not the same thing. Part of the mass in Uranium is in the binding energy. That energy is being released in the form of photons and a few bits and parts of elements flying off. In butter most of it is carbon (in weight) and hydrogen. Hydrogen can't be split, carbon has about the lowest binding energy so breaking that one up won't give much. Melting together the hydrogen into carbon would release quite a bit of energy, but conditions in a pack of butter do not favor such: hydrogen atoms are far too far away from each other in comparison with the bundle of protons/neutrons in Uranium (just about the distance as close you have to get those H atoms to each other to have a stable nucleuos)
  4. Mar 31, 2013 #3
    Thanks Ger. If I may, I would like to put this in a form that helps me understand just what you are saying. Gravity holds my mass against the earth. There is an energy or potential difference between me on earth and me out in space. My mass remains the same but when I'm on earth I contain more energy. This is the energy required to separate me from the earth as like binding energy. The farther I'm away from the earth, the less energy (binding energy) I contain. Am I out to lunch here?

  5. Mar 31, 2013 #4


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    Less. The binding energy subtracts from your total energy. To boost you into space I have to add energy, and now you contain more. If you should fall back >splat< that amount of energy is released.
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