Teachers' Domain; Physical Science/Engineering; Nuclear Reaction: Fission

In July of 1945 the United States Army assembled some of the world's greatest physicists in the New Mexican desert at Los Alamos. Armed with an understanding of Chain Reaction and Einstein's famous phenomenon equals MC squared. The goal was to create an atomic bomb before the enemy. In a short time scientific theories were turned into something of enormous power. When the United States dropped nuclear bombs on Hiroshima and Nagasaki. More than 100000 people were killed in Hiroshima alone. The atomic age had begun. After the war scientists hope to use nuclear power at home. This time harnessing the power of the nucleus for cheap clean energy. By nine hundred

fifty one scientists and engineers had taken the same technology that destroyed Hiroshima and Nagasaki and used it to generate electricity. There was a very exciting field we thought it would be the leading method of making electricity throughout the world. You have a very small amount of space 12 feet tall to 12 feet in diameter and you produce enough electricity to run a large city in that small space. So the energy source is extremely concentrated which is one of its great benefits. The principal element used in nuclear fission is uranium 235 before the war. Scientists discovered a special property of this particular isotope of uranium. When a neutron strikes the nucleus of U-235. It causes the atom to fission or split releasing more neutrons that can split other uranium atoms. Each fission releases large amounts of energy.

By making small pellets containing uranium 235. Loading them into fuel rods and putting them into the nuclear core. Scientists are able to create a self-sustaining chain reaction that produces enormous amounts of energy. This energy is used to heat water. Which produces steam that drives turbines generating electricity. 20 percent of the electricity consumed in the United States now comes from nuclear power. But debate continues about plant safety and the risks associated with transporting and storing nuclear waste.