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Nuclear Bombs Essay, Research Paper
In the early 1950’s many above ground nuclear tests occurred
exposing radiation to millions of children. Because of these happenings,
the government had reason to believe that there will be an increased incidence of thyroid cancer to these children. The children got contaminated by many sources. One which was, I-131 contaminated the grass which was consumed by the cows. The cows then excreted the milk, which was fed to children where it was concentrated in the thyroid and caused cancer. They also tested for other types of Iodine in the radiation (I-131, I-132, I-133) as well as other types of radiation such as radioactive cesium which may have been inhaled and caused cancer.
There are several types of Atomic Bombs, one being the ?Little Boy’. It takes about a minute to explode after being released. The ?Little Boy’ generates an enormous amount of energy in terms of air
pressure and heat. It also releases a huge amount of radiation ( gamma
ray and neutrons) that caused severe human injury. The winds are also
capable of destroying most houses and buildings within a 1.5 mile radius.
The United States of America is a very large country with a very well-known reputation and are known not to mess with. The United States of America has exploded half of all Nuclear Bombs. The first ever nuclear device was the trinity which exploded over a desert in Nevada, July 1945. The only 2 nuclear bombs used against people are the ?Little Boy’ and the ?Fat Man’. The United States of America is the leader of all countries on nuclear explosions with 1143 explosions to its name. Next is the USSR with 588, France was third with 203, while Britain and China are tied at 46 a piece.
The History of Nuclear Bombs:
On August second 1939, just before the beginning of World War II, Albert Einstein wrote to then president Franklin D. Roosevelt. Einstein and several other scientists told Roosevelt of efforts in Germany to purify U-235 which could be used in the construction of a nuclear bomb, the Atomic bomb. The president of the U.S.A. took this into serious consideration, this was called the Manhattan Project. The Manhattan project was an attempt to make a very powerful nuclear weapon.
The most complicated part of this project was extracting the Uranium. They needed Uranium-235 to start the chain reaction required, but the conversion from Uranium ore to Uranium metal is 500:1. This made it virtually impossible to separate U-235 and U-238. No ordinary chemical extraction could separate the two isotopes so they had to use mechanical methods.
Ernest O. Lawrence invented a process for extracting these isotopes using magnetic force. After the magnetic separation they would use a gas centrifuge to further separate the lighter U-235 from the heavy, non- fissionable U-238.
Over the course of 6 years, ranging from 1939 to 1945, more than 2- billion dollars were spent on the Manhattan Project. One man was the single biggest help in the Manhattan Project and his name was, J. Robert Oppenheimer.
Nuclear Fission/Nuclear Fusion:
There are two types of atomic explosions that can be facilitated by
U-235; fission and fusion. Fission, simply put, is a nuclear reaction in which an atomic nucleus splits into fragments, usually two fragments of comparable mass, with the evolution of approximately 100 million to several hundred million volts of energy. This energy is expelled explosively and violently in the atomic bomb. A fusion reaction is invariably started with a fission reaction, but unlike the fission reaction, the fusion (Hydrogen) bomb derives its power from the fusing of nuclei of various hydrogen isotopes in the formation of helium nuclei. The massive power behind the reaction in an atomic bomb arises from forces that hold the atom together.
Atoms are comprised of three sub-atomic particles. Protons and neutrons cluster together to form the nucleus (central mass) of the atom while the electrons orbit the nucleus much like planets orbit around the sun. The electrons are the part of the atom that determine the stability.
There are two types of Uranium isotopes. Natural Uranium consists mostly of isotope U-238, which has 92 protons and 146 neutrons (92+146=238). Mixed with this isotope, one will ind a 0.6% accumulation of U-235, which has only 143 neutrons (the number of protons does not change because it is the same element). This isotope, unlike U-238, has atoms that can split, thus it is called “fissionable” and useful in making atomic bombs.
U-238 can be neutron-saturated to produce Plutonium (Pu-239). Plutonium is fissionable and can be used in place of U-235.
Both isotopes of Uranium are naturally radioactive. Their bulky atoms disintegrate over a period of time. Given enough time, (over 100,000 years or more) Uranium will eventually lose so many particles that it will turn into metal lead. However, this process can be accelerated. This process is known as the chain reaction. Instead of disintegrating slowly, the atoms are forcibly split by neutrons forcing their way into the nucleus. A U-235 atom is so unstable that a blow from a single neutron is enough to split it causing a chain reaction. When a chain reaction occurs, the Uranium atom splits into two smaller atoms of different elements, such as Barium and Krypton.
The Mechanism of a Bomb:
An ordinary aircraft altimeter uses a type of Aneroid Barometer which measures the changes in air pressure at different heights. However, changes in air pressure due to the weather can adversely affect the altimeter’s readings. It is far more favorable to use a radar altimeter for enhanced accuracy when the bomb reaches Ground Zero.
As the descent of the bomb begins, the altimeter transmitter will send out a pulse starting at 4200 MHz. By the time that pulse has returned, the altimeter transmitter will be emitting a higher frequency. The difference depends on how long the pulse has taken to do the return journey. When these two frequencies are mixed electronically, a new frequency emerges.
Types of Nuclear Bombs:
Refer to pages preceding the diagrams >>>>>
Detonation:
The detonating head that is seated in the conventional explosive charge is similar to the standard-issue blasting cap. It merely serves as a catalyst to bring about a greater explosion. Calibration of this device is essential. Too small of a detonating head will only cause a colossal dud that will be doubly dangerous because someone has to disarm and re-fit the bomb with another detonating head. The detonating head will receive an electric charge from either the air pressure detonator or the radar altimeter’s coordinating detonator.
The air pressure detonator can be a very complex mechanism, but for all practical purposes, a simpler model can be used. A simple piece of very thin magnetized metal can be used as an air pressure detonator.
The Uranium detonator is comprised of 2 parts. Larger mass is spherical and concave. Smaller mass is precisely the size and shape of the ?missing’ section of the larger mass. Upon detonation of conventional explosive, the smaller mass is violently injected and welded to the larger mass. Supercritical mass is reached, chain reaction follows in one millionth of a second.
The Plutonium detonator is comprised of 32 individual 45 degree pie- shaped sections of Plutonium surrounding a Beryllium/Polonium mixture. These 32 sections together form a sphere. All of these sections must have precisely equal mass as the others. The shape of the detonator resembles a soccer ball.
Nuclear Bombs and Countries:
The United states of America is a very large country with a very well- known reputation. The U.S.A. has exploded half of all nuclear bombs. The first ever nuclear device was the trinity which exploded over a desert in Nevada, July 1945. The only 2 nuclear bombs ever used against enemies were the ?Little Boy’ and the ?Fat Man’. The U.S.A. is the leader of all countries in nuclear explosions with 1143 to its name. Next is the USSR with 588, France was third with 203, while Britain and China are tied at 46 a piece.
The Effects of Nuclear Bombs:
In the early 1950’s many above ground nuclear tests occurred exposing radiation to millions of children. Because of these happenings, the government had reason to believe that there was an increased incidence of thyroid cancer to these children. The children got contaminated by many sources. One which was, I-131 contaminating the grass which was fed to the cows. The cows then excreted the milk. The milk was fed to the children causing thyroid cancer. Most Nuclear tests take place beneath the surface of the earth during our times for our safety.