fission/fusion

• Fission and Fusion
• Nuclear Fission-Splitting a Large, Unstable Nucleus
• When the atom splits it forms smaller atoms that have less energy in the nucleus
• Energy is also released when an atom splits
• The energy released to the fragments of the products is carried away by the remaining fragments and the other decay products can be used to heat water, making steam to turn turbines and generate electricity
• The amount of energy produced by fission in such reactors is controlled by control rods, which are lowered and raised to absorb neutrons and slow down the chain reaction and control the amount of energy released
• Uncontrolled chain reactions quickly lead to lots of energy being released, as in nuclear explosions-this is how nuclear weapons work
• Nuclear Fusion-Joining Small Nuclei
• In nuclear fusion, two light nuclei collide at high speed and fuse (join) to create a larger, heavier nucleus
• The heavier nucleus produced by fusion does not have as much mass as the two lighter nuclei did. Some of the mass of the lighter nuclei is converted to energy
• Fusion releases a lot of energy (more than fission for a given mass of fuel)
• So far, scientists haven't found a way of using fusion to generate energy for us to use. The temperatures and pressures needed for fusion are so high that fusion reactors are really hard and expensive to build
• Fission rarely occurs spontaneously, it often needs a prod to get it going
• Forced fission reaction


  Steps in forced fission reaction