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Homework Help: Conditions for nuclear fission

  1. Jun 3, 2012 #1
    1. The problem statement, all variables and given/known data
    not an equation as such. new to this but i wanted to know what the conditions for nuclear fission are? other than high temperatue and pressure

    2. Relevant equations
    "state the conditions for fusion and hence explain why it has proved difficult to maintain a sustainable reaction in a practical fusion reactor

    3. The attempt at a solution
    well i know high temp and pressure are needed to overcome repulsive forces. the marking scheme says ''nuclei come close to fuse/for strong force to act'' and i don't understand what that means
  2. jcsd
  3. Jun 3, 2012 #2
    There is a "potential barrier" between any two nucleons, which is the sum of the repulsive Coulomb forces and the attractive strong forces. The strong force is different fundamental force, due to the fact that protons are composed of quarks which carry color charge. I would look up the wiki article on this for more details (search for Quantum Chromodynamics).

    The short of it though, at far distances the Coulomb repulsion dominates, and at a certain critical distance the force between the protons suddenly becomes attractive - the protons must have enough energy to overcome the Coulomb repulsion and get close enough and they will snap together, and release energy.
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