Nuclear reactor, Science

Nuclear Reactor:

Nuclear fission can be maintaned as a controlled cjiain reaction in a nuclear reactor to produce  energy. Fermi had found from experiment  that slower moving neutrons were more effective in causing nuclearfission.  But most neutrons produced by the splitting of the nuclei are quite fast. A way was required to slow  them down. It was found that certain materials slow down the neutrons. Graphite. a pure form of carbon, is one such material. Such materials are  called moderators. There was still the problem of controlling the chain reaction so  created,  that is, to stop the  , reaction or allow it to proceed at will. Materials which absorb neutrons would serve to control the reaction. The neutrons absorbed by  such materials would be removed and would no longer split atomic nuclei. And the reaction would be controlled. The material usually chosen as an absorber of neutrons, is cadmium or boron steel. In a nuclear reactor . rod-like containers of Uranium-235 are inserted in holes made in a huge block of graphite. The graphite block slows down neutrons to enhance the chain reaction. Control rods of cadmium are also inserted into the graphite block. When pushed out, they absorb fewer neutrons and the reaction is speeded up. The problem, then, is to remove the heat and use it to generate electrical energy. This is achieved by circulating water, or liquid sodium to absorb the heat generated  in the graphite block. This heat may generate steam, which can turn a turbine (a wheel with slanting blades) anqhe  connected electrical generator.  

795_Nuclear Reactor.png

Today we have reactors capable of yielding power upto 500 Megawatts. Smaller  reactors which give 1 to 5 Megawatt power are  mostly used for reseasch work. The large ones are used for producing electricity, and driving submarines,  or ships. From the uranium rods used in the reactor, another fissionable material like Plutonium 239 may be obtained.

Posted Date: 9/29/2012 1:59:28 AM | Location : United States







Related Discussions:- Nuclear reactor, Assignment Help, Ask Question on Nuclear reactor, Get Answer, Expert's Help, Nuclear reactor Discussions

Write discussion on Nuclear reactor
Your posts are moderated
Related Questions
How would I give a presentation to the public on the use of Malathion as a means to control mosquitos

Air Pollution Air pollution  is one of the major problems created by modern man.  It  is estimated that about 100 million tons of waste are poured  into our atmosphere each y

Define the Absorption of Amino Acid Proteins are absorbed in the form of amino acids. Amino acid transport occurs 'only in the presence of simultaneous sodium transport. Carrie

What is the difference among the geoid and the surface of the earth? The geoid is an visualize surface that equal with the average (mean) sea level around the world. Thus, i

Examining sand with a magnifying glass Study a small amount of sand with a magnifying glass or under the low power of a microscope if there is single available. The nearly colo

Ask quesExplain that your intention is to investigate a variety of combinations of pipe material, insulation material and size which you could potentially consider when deciding on


descibe the factors which decidethe broad area of scientific activity?

Q. What are the preliminary steps involved during preparation of raw materials? Preliminary steps involved during preparation of raw materials include cleaning, peeling, cuttin

A simple mercury barometer Seal single end of a glass tube about 80 cm in length by rotating it in a gas flame. The tube should be held as almost vertical as possible. Join a s