The two masses of U had to combine with one another quickly enough to avoid the spontaneous fission of the atoms, which would cause the bomb to fizzle, and thus fail to explode. Powered by plutonium , Fat Man could not use the same gun-type design that allowed Little Boy to explode effectively - the form of plutonium collected from the nuclear reactors at Hanford, WA for the bomb would not allow for this strategy. The Hanford plutonium emerged from the reactors less pure than the initial plutonium extracted from Ernest O.
Thus, a new design was required. Physicist Seth Neddermeyer at Los Alamos constructed a design for the plutonium bomb that used conventional explosives around a central plutonium mass to quickly squeeze and consolidate the plutonium, increasing the pressure and density of the substance.
An increased density allowed the plutonium to reach its critical mass, firing neutrons and allowing the fission chain reaction to proceed. To detonate the bomb, the explosives were ignited, releasing a shock wave that compressed the inner plutonium and led to its explosion. Browse our collection of oral histories with workers, families, service members, and more about their experiences in the Manhattan Project. Skip to main content. Science Behind the Atom Bomb.
History Page Type:. Thursday, June 5, Fission The isotopes uranium and plutonium were selected by the atomic scientists because they readily undergo fission. Due to the high temperatures required to initiate a nuclear fusion reaction, the process is often referred to as a thermonuclear explosion. This is typically done with the isotopes of hydrogen deuterium and tritium which fuse together to form Helium atoms. The first hydrogen bomb was exploded on 1st November, at the small island of Eniwetok in the Marshall Islands.
Its destructive power was several megatons of TNT. The blast produced a light brighter than a thousand suns and a heatwave felt 50 kilometres away. The Soviet Union detonated a hydrogen bomb in the megaton range in August The US exploded a 15 megaton hydrogen bomb on 1st March, It had a fireball of 4.
Page 7 of Previous Next. The inherent radioactivity of uranium will then release a neutron, which will bombard another atom of U to produce the unstable uranium, which undergoes fission, releases further neutrons, and continues the process.
The uranium atom can split any one of dozens of different ways, as long as the atomic weights add up to uranium plus the extra neutron. The following equation shows one possible split, namely into strontium 95 Sr , xenon Xe , and two neutrons n , plus energy:. The immediate energy release per atom is about million electron volts Me.
Of the energy produced, 93 percent is the kinetic energy of the charged fission fragments flying away from each other, mutually repelled by the positive charge of their protons. This initial kinetic energy imparts an initial speed of about 12, kilometers per second. Here, their motion is converted into X-ray heat, a process which takes about a millionth of a second. By this time, the material in the core and tamper of the bomb is several meters in diameter and has been converted to plasma at a temperature of tens of millions of degrees.
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