The critical mass is the maximum size a sample of uranium ore can reach. If the sample is larger then the critical mass it will start an uncontrolled reaction. 99.3% of uranium ore is made up of uranium-238 and 0.7% is uranium-235. Nuclear fusion is the process in which two nuclei fuse together to form a larger nuclei. Hydrogen atoms are usually used in fusion reactions.
Nuclear Power Producing energy from a nuclear power plant is very complicated. The process of nuclear energy involves the fission of atoms, the release of energy from fission as heat, and the transfer of heat to electricity in power plants. The process of splitting the atom is called nuclear fission. Fission can take place in many different kinds of atoms. This explanation uses Uranium - 235, the atom most commonly used in nuclear reactors.
The most important isotope is plutonium 239, or Pu-239. When struck by a neutron, this isotope undergoes a process called fission. In fission, When struck by a neutron, the nucleus of the plutonium atom is split into two nearly equal parts, and energy is released. Although the energy released by one atom is not much, the splitting of the nucleus releases more neutrons, which strike more plutonium atoms. This process, called a chain- reaction, produces enormous amounts of energy.
fragments" as well as less massive particles as the Neutrons). In the Nuclear Reactors this splitting is induced by the interaction of a neutron with a fissionable nucleus. Under suitable conditions, a "chain" reaction of fission in which events may be sustained. The energy released from the fission reactions provide heat, part of which is ultimately converted into electricity. In the present day Nuclear power plants, this heat is removed from the Nuclear fuel by water that is pumped past rods containing fuel.
Compare Nuclear Fusion vs. Nuclear Fission Nuclear energy must be a consideration for the future with the rapidly depleting supply of fossil fuels. This type of energy can be created through nuclear fission and nuclear fusion. Nuclear fission is the splitting of a heavy atom into two or more parts, releasing huge amounts of energy. The release of energy can be controlled and captured for generating electricity. Nuclear fusion involves bombarding hydrogen atoms together to form helium.
The fuel is usually either Uranium-235 or plutomium-239. Uranium-235 has an extra property that makes it useful for both nuclear power production and for nuclear bombs - it is one of the few materials that can undergo induced fission. If a neutron runs into a Uranium nucleus, the nucleus will absorb the neutron, become unstable and split immediately. As soon as the nucleus captures the neutron, it splits into two lighter atoms and throws off 2 or 3 new neutrons. These neutrons then hit other uranium atoms and a chain reaction is started.
See How Nuclear Radiation Works for complete details. Nuclear Fission The animation below shows a uranium-235 nucleus with a neutron approaching from the top. As soon as the nucleus captures the neutron, it splits into two lighter atoms and throws off two or three new neutrons (the number of ejected neutrons depends on how the U-235 atom happens to split).
Fission Weapons (Atomic Bombs) Fission weapons, or "Atomic Bombs", are based on nuclear fission. Nuclear fission occurs when the nuclei of certain isotopes of heavy elements (such as uranium or plutonium) capture neutrons. The result is that the nuclei become unstable and break apart into two smaller nuclei. This process converts some of the mass into energy and releases varying numbers of neutrons that go on to collide with other nuclei causing them to break apart and so on and so on. In nature this process is irrelevant due to the low natural occurrence and densities of radioactive isotopes.
the fission that is produced is when a heavy element splits in half or is halved into two smaller nuclei, the power of the fission is located by the rate of the splitting of the nuclei at once which causes watts of electricity to be forced into the energy type. Energy that is released by the nuclear fission matches almost completely to that of the properties of kinetic fission particles, only that the properties of the nuclear energies nucleus are radioactive. These radioactive nucleuses can be contained and used as fuel for the power. Most of this power is fueled by uranium isotopes. These isotopes are highly radioactive.
The second type uses fission reactions to begin nuclear fusion reactions which in turn produce a large amount of the total energy output. Such fusion weapons are known as thermonuclear weapons or hydrogen bombs (abbreviated as H-bombs). Figure 1.2 shows the structure of such a weapon. There are other types of nuclear weapons such as a boosted fission weapon and a neutron bomb. Most variation in nuclear weapon design is for the purpose of achieving different yields for different situations, and to manipulating design elements in order to minimize weapon size (Wikipedia 2013).