Explanations of fission reactions always say there’s a tremendous amount of energy released, but where is that energy? So, if an atom of u-235 was split in a complete vacuum, in what forms(s) would the released energy be?
In: 3
From wikipedia:
> When a uranium nucleus fissions into two daughter nuclei fragments, about 0.1 percent of the mass of the uranium nucleus[9] appears as the fission energy of ~200 MeV. For uranium-235 (total mean fission energy 202.79 MeV[10]), typically ~169 MeV appears as the kinetic energy of the daughter nuclei, which fly apart at about 3% of the speed of light, due to Coulomb repulsion. Also, an average of 2.5 neutrons are emitted, with a mean kinetic energy per neutron of ~2 MeV (total of 4.8 MeV).[11] The fission reaction also releases ~7 MeV in prompt gamma ray photons. The latter figure means that a nuclear fission explosion or criticality accident emits about 3.5% of its energy as gamma rays, less than 2.5% of its energy as fast neutrons (total of both types of radiation ~6%), and the rest as kinetic energy of fission fragments (this appears almost immediately when the fragments impact surrounding matter, as simple heat).
So, when U235 is hit by a neutron, it splits and a tiny bit of its mass converts into energy per the famous equation of Einstein. Most of this energy is tied up in the parts of the atom formerly known as uranium getting flung *real fucking hard* away from each other and usually into other stuff. This is effectively heat. A bit of the energy goes into making some gamma frequency photons (the funny invisible light that makes your DNA say adiós) and some neutrons which can go on to hit other uranium atoms. An even smaller portion of the energy is tied up in the unstable resulting atoms and will be released over time as they decay.
Latest Answers