nuclear energy?

Question

sorry again i need help... what is nuclear energy...?... do we need it?..

Answer 1

What is nuclear energy?
Nuclear energy is energy that comes from the nucleus (core) of an atom. Atoms are the particles that make up all objects in the universe. Atoms consist of neutrons, protons, and electrons.

Nuclear energy is released from an atom through one of two processes: nuclear fusion or nuclear fission. In nuclear fusion, energy is released when the nuclei of atoms are combined or fused together. This is how the sun produces energy. In nuclear fission, energy is released when the nuclei of atoms are split apart. Nuclear fission is the only method currently used by nuclear plants to generate electricity.

The fuel most widely used by nuclear power plants for fissioning is uranium. Uranium is the heaviest of the 92 naturally occurring elements and is classified as a metal. It is also one of the few elements that is easily fissioned. Uranium was formed when the earth was created and is found in rocks all over the world. Rocks that contain a lot of uranium are called uranium ore, or pitch-blende. Uranium, although abundant, is a nonrenewable energy source.

Two forms (isotopes) of uranium are found in nature, uranium-235 and uranium-238. These numbers refer to the number of neutrons and protons in each atom.

Uranium-235 is the form commonly used for energy production because, unlike uranium-238, its nucleus splits easily when bombarded by a neutron. During fissioning, the uranium-235 atom absorbs a bombarding neutron, causing its nucleus to split apart into two atoms of lighter weight. At the same time, the fission reaction releases energy in the form of heat, radiation, and more neutrons. The newly released neutrons go on to bombard other uranium atoms, and the process repeats itself over and over. This is called a chain reaction.

Answer 2

Nuclear energy is taking the heat generated by the nuclear fission of a radioactive substance, usually Uranium. The heat is absorbed by water which is turned into steam and powers a turbine, much like any other power plant.

It is a powerful energy supply, HOWEVER the problem comes with what to do with the radioactive waste. Nuclear power plants create tons and tons of the stuff each year, and we have no idea how to really use it or dispose of it. So all we can do is shove it underground in a mountain for a few hundred thousand years until it becomes safe again.

Answer 3

Nuclear energy, or atomic energy, is energy obtained by re-arranging the nuclei of atoms, as opposed to changing chemical combinations. The first such that was discovered was the fission of a certain kind of uranium metal called U-235. Later, a similar result was obtained with plutonium-239, which is almost nonexistent in nature but can be made in a nuclear reactor. U-235 is used in power reactors all over the world to produce electricity.

Nuclear energy can also be obtained from fusion -- combining light elements to make heavier ones. So far, this process has been used for explosives but not for use in power production.

The world's supply of fossil fuel energy is being depleted at a rapid rate, and nuclear energy will become more and more important as a replacement.

Answer 4

Current nuclear power plants use the fission of uranium to generate heat, then use the heat to boil water to produce steam to run turbines. The turbines generate the electrical power.

The poster above referred to two "huge accidents". I presume she means Chernobyl (which is in the former Soviet Union) and Three Mile Island. You can google them to get more information, but in short:

Chernobyl - Typical shoddy Soviet design. They used something called graphite in the reactor, and it caught fire. The same thing happened in England in the Windscale power plant about twenty years before Chernobyl. The difference is that the English aren't stupid - they had a building around the reactor to contain the radioactive smoke from the fire, so no major exposure occurred. The Soviets didn't, and they contaminated a huge area. The English abandoned that type of reactor design as inherently unsafe. The Soviet's didn't care, because it was cheap.

Three Mile Island - Reactor operators missed critical information and ignored their instruments, assuming that they were wrong. They basically did everything wrong that they could, and managed to damage the reactor core in the process. Despite this, the maximum dose received by any member of the public was less than one would get from a single dental x-ray at the time. Media hype and general Luddite fears blew it up out of all proportion.

Nuclear power can be safe and is much less damaging to the environment, taken all for all, than any other form of power. Do we need it? Probably not. But life will be a lot easier for a lot of people if we use it intelligently.

Edit: Depending on power usage, the radioactive waste generated by a single plant in a year can be refined down to about a cubic meter. If this qualifies as "tons and tons", then I guess the poster below is right. The waste is radioactive, but so is the stuff taken out of the ground to make the fuel in the first place - you know, the stuff God put there. The waste is, generally, more radioactive than the original ore, but this is a good thing. Higher specific radioactivity means a shorter half-life, meaning it becomes inert more quickly than if we had left it alone.

Nuclear waste is only a problem because people don't bother to educate themselves on the topic. If Jane Fonda opposes it, that's good enough for most of them.

Answer 5

One example of nuclear energy is using plutonium rods to heat water that makes steam that runs a turbine that turns a generator producing electricity, There are different types of nuclear reactions but they all convert steam into mechanical energy that turns the generator producing power. Hope I helped.

Answer 6

It is energy created from heat generated by nuclear fission.. 90% of the electricity in France is made that way.. Someday we may discover how to do nuclear fission (That is what the sun does). If we do, we will have unlimited power without any pollution..

Answer 7

Nuclear energy is what makes the sun and stars shine. Hydrogen, atoms (the simplest and lightest element) are squeezed together very tightly by the enormous gravity of sun sized bodies and they fuse with each other creating the next heaviest element which is Helium. For various and sundry reasons, when this transformation takes place, the resulting Helium atom is slightly lighter than the Hydrogen atoms that were combined to make it. This slight weight difference (about 5%) is nuclear energy, and is radiated away from the atom in the form of heat and light. If a star is large enough, this process continues as it ages, eventually using up most of it's hydrogen. This causes it to dim and begin shrinking because its like a balloon, and as the radiated heat and light become less, it's hard for it to stay inflated. As it shrinks, gravitational compression begins reheating it, and the Helium atoms begin to fuse at the core. The star swells back up, because the Helium burns even hotter. Also, and I'm simplifying this, the star becomes larger and more red in color and is called a red giant now. There's still a lot of hydrogen in outer atmosphere of the star, but its lighter than the inner cord where the nuclear fires are burning helium, and it gets pushed away and cools slightly. This process of expansion and contraction happens many times as a star fuses it way down the periodic table of elements, using one up, then making a heavier one, until it finally gets to iron. That's the last element that can be fused and energy extracted from the process. Without an energy source to keep it inflated, gravity takes over and the star begins to shrink rapidly. It gets so hot that the old hydrogen atmosphere comes back into play. It reignites and creates a tremendous explosion. (This is a nova, not to be confused with a supernova which is different and can result in neutron stars and black holes) The fusion process continues then, the iron coming together so hard and hot that it starts making heavier and heavier elements. Gold, silver, lead, all the elements that are heavier than iron. There is a difference in this fusion though. Instead of releasing energy when the new element is made, energy is absorbed. The new atoms are slightly heavier than the lighter atoms that created them, and that extra weight represents absorbed energy. The star will do this many times, over hundreds of millions of years, slowly ejecting its mass into space during its explosive phases. (Just for your information, this is how we know that our sun is a second generation star. It contains traces of the heavy elements that could have only come from previous stars. It's these very elements that make life possible.) Among the new elements that have been made in the star, there are some that are so heavy, that they are relatively easy to break apart. Certain isotopes of Uranium are among these. These atoms are very large, and atoms don't like to be this large and pieces break off easy. They are said to be radioactive, which is their way of saying they want to be smaller and lighter. There are reasons for this that deal with things like charge that I won't go into. Now, we have these heavy atoms and we've learned that if they are brought together in a large enough mass (called critical mass) the pieces being ejected from them will begin interacting and create a self sustaining reaction. This is called fission, which is the exact opposite of fusion, and what's happening is that the original energy of their creation is being released as they break down into lighter elements. This is what runs nuclear power plants. They control the reaction by keeping the uranium fuel rods somewhat below critical mass and dampened by things like carbon and water that absorbs some of the decay products. If you bring larger amounts of this same uranium (in a slightly more purified state) together very rapidly, as with explosive force, you have an atom bomb. A hydrogen bomb is made in a similar fashion. A series of fission explosions detonate a core of light atoms and they fuse and release energy. The bomb is greatly enhanced as following the fusion reaction, another fission reaction takes place. These are called fission, fusion, fission bombs and there is virtually no limit on the size of the explosion that can be obtained.
Do we need nuclear power? Yes and no. The sun is a nuclear power plant, and it's just where I like it. 93,000,000 million miles away. We are literally awash in energy on this planet. We could easily get off oil, coal, and nuclear energy if we devoted the resource and will to the task. These would mega projects, that would take advantage of wind, tide, desert, hydrothermal, biomass, and a half dozen other benign technologies that are well within our grasp. This would additionally go a long ways in elevating unemployment, not to mention it would solve the middle east problem in just a few short years. I won't even mention global warming, which is real and will kill or destroy the lives of unknown generations not yet born. Make no mistake. Nuclear power which is clean in some ways, is potentially the dirtiest and most costly form of power imaginable. It's by products are bombs and toxic waste that stays toxic for tens of thousands of years. We need to take advantage of the nuclear power plant in the sky. It's there, it's clean, and it's safe. (I won't mention that except for maintenance, the power is absolutely free once the infrastructure is paid for)

Answer 8

nuclear energy is potentially a good thing, but 2 huge accidents have caused people to fear the use of it. the power plants have to be closely monitored and regulated and americans are too stupid to be able to do that properly, but other countries use nuclear power more (i think european countries).