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The Threat Of Nuclear Weapons Essay Research

The Threat Of Nuclear Weapons Essay, Research Paper


Ever since the first nuclear weapon was built in 1945, nuclear war has been a threat. The two major


nuclear powers in the world today are the Soviet Union and the United States. If a war ever broke out between


the two, which involved the use of nuclear weapons, the whole world would suffer from the effects. In this


report I am going to prove that nuclear weapons are a threat to all of us.


A nuclear weapon is any device that causes an explosion by the release of the energy in an atom.


They are much more powerful than any conventional or “non nuclear” weapons. Nuclear weapons are divided


into two groups: fission weapons, which are often called atom bombs, and thermonuclear or fusion weapons,


which are often called hydrogen bombs because that is what they are made of.


FISSION WEAPONS


Fission weapons cause an explosion by the splitting of atomic nuclei. This happens when a neutron


collides with the nucleus of an atom. The protons in the nucleus are transformed into a great amount of energy


and two or three more neutrons are sent out, which go on to split other nuclei. If this continues a process called


a chain reaction will occur. When this happens a fission explosion is the result. To form a chain reaction, a


certain amount of material is needed. This amount is known as the critical mass. If the amount is too small it


is known as a subcritical mass. The critical mass of a material depends on its purity. The materials used in


making fission weapons are uranium and plutonium. They are the only elements able to be used in making a


fission weapon.


There are two different ways to make a fission weapon: the gun-type method and the implosion


method. In the gun-type method, two pieces of material, each having a subcritical mass, are placed at opposite


ends of a metal cylinder. One of the pieces has a powerful, nonnuclear explosive behind it that explodes on


impact and drives the piece into the one at the other end. The atoms in the material the collide and start a


chain reaction. In the implosion method a ball of either uranium or plutonium is surrounded by a large amount


of nonnuclear explosive. When triggered it compresses the nuclear material, which also causes a chain


reaction.


FUSION WEAPONS


Thermonuclear or fusion weapons get their destructive power from the combining of light atoms.


Hydrogen, the lightest element, is used in making fusion weapons. When the atoms of the element fuse, they


release a great amount of energy. The only problem is that the element must be heated to a temperature of 50


million degrees Celsius. The only way to do this, without using more energy than is produced, is to use a


fission explosion. So, a ball of hydrogen is surrounded by either uranium or plutonium and then by a non


nuclear explosive. When the explosive is set off it causes the uranium or plutonium to fission, which in turn


causes the hydrogen to fuse.


HISTORY


In 1939, the U.S. government became concerned that the Nazi Germans may be capable of building a


nuclear weapon, so upon joining World War II, the United Sates began a secret operation called the Manhattan


Project to build their own nuclear weapon. The first experimental nuclear weapon was exploded on July


16,1945, by J. Robert Oppenheimer. It was a 22 kiloton implosion-type device. This test convinced the U.S.


government that nuclear weapons could be used in war. On August 6, 1945, the United States used the first


nuclear weapon on the Japanese city of Hiroshima. It was a 13 kiloton gun-type fission bomb. Three days


later, the United States dropped a 22 kiloton implosion-type fission bomb on another Japanese city called


Nagasaki. On August 14, eight days after the first bomb was dropped, the Japanese surrendered, which


brought an end to World War II.


EFFECTS


The three main effects that would follow a nuclear explosion are blast, thermal radiation or heat, and


radiation. The very first thing to happen is the formation of a fireball. The fireball gives off the thermal


radiation that vaporizes anything within a quarter mile and ignites flammable materials within ten miles. The


thermal radiation can cause eye injuries as well as skin burns called flash burns. Between 20 and 30 per cent


of the deaths at Hiroshima and Nagasaki were caused by flash burns. When the fireball begins to dissipate it


forms a blast wave that travels away from the explosion at speeds up to 400 miles per hour. This destroys most


building within 6 miles. It also kills most people within 3 miles and severely injures or kills most people up to


6 miles away. Then comes the radiation. It is made up of neutrons that were left over after the explosion.


When these neutrons come in contact with living cells they damage or even destroy them. A person exposed to


large amounts of radiation will usually die.


Some scientists believe that the debris and smoke from the fires after a nuclear war would cause a


worldwide cooling of the planet, which is known as a nuclear winter. For this reason, the nations at war would


not be the only ones to suffer.



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