L.Lyon+Nuclear+Powerpoint

=//__How an Atomic Bomb Works__//=

Atomic bombs contain the strong and weak forces that hold an atoms nucleus together. Mainly, these nuclei are unstable, and release energy in two basic ways: nuclear fusion, and nuclear fission. Nuclear fusion is the process of bringing two small atoms (normally hydrogen isotopes, tritium and deuterium) and creating one larger atom (normally helium). In nuclear fission, you split the atom, creating two remaining particle with a neutron. Fission generally includes a uranium or plutonium isotope. The reaction to both of these procedures, releases an immense amounts of heat energy and radiation.

An atomic bomb works when the process of nuclear fusion or fission creates a chain reaction. For this to happen you can’t just have a couple of atoms, an atomic bomb would need many atoms with heavy nuclei, tightly packed together. When a neutron hits the nuclei, it either creates fusion or fission, causing the necessary chain reaction. The first atomic explosion occurred on 16 July 1945, during a test under the direction of General Leslie R. Groves of the US Army.

To build an atomic bomb, you need a source of fission or fusion-able fuel. You also need a triggering device. These triggers could be neutrons, guns, and implosions. Most of the fuel also needs to be able to fission or fuse before the explosion occurs for the best result. These are all used in general fission, fusion, and the atomic bombs dropped over Japan in 1945.

The atomic reaction occurs when a neutron is captured by an atom (normally of uranium-235), causing it to break (fission), and 2 more neutrons to be rejected, and emitting gamma radiation. For this reaction to be effective, the uranium 235 must be enriched, consisting of at least 90% uranium 235. The process of the neutron splitting an atom happens extremely fast. It takes merely a couple of picoseconds (or 1*10e-12 seconds). To prevent premature discharge, the fuel must be kept in non-fissionable sub masses, in a fission bomb.

===__//BIBLIOGRAPHY// http://www.howstuffworks.com/nuclear-bomb.htm http://www.wisegeek.com/how-does-an-atomic-bomb-work.htm http://www.zamandayolculuk.com/cetinbal/FJ/fissionp.png http://www.lancs.ac.uk/ug/bloomer/nuclearpower/fusion.jpg http://www.pa.msu.edu/~yang/NuclearBomb.jpg__===