Hiroshima, Japan, atomic bomb over

This year there were completed the first three atomic (or nuclear) bombs. The first bomb was successfully exploded in the New Mexico desert on July 16, 1945, and a second over Hiroshima, Japan on Aug 6, 1945, and the third over Nagasaki on Aug 9, 1945. The bombs were of Fission Type and of tens of kilotons (thousands of tons of TNT equivalent) (Vol 1 of Encycl, p A499-L)... 

II. On August 6, 1945, an atomic bomb (nicknamed as Little Boy ) was dropped by an American B-29 bomber (Enola Gay) over Hiroshima, Japan instantly killing more than 70000 people. On August 9, 1945, the USA dropped a second atomic bomb (nicknamed Fat Man ) killing some 40000 people in Nagasaki, Japan. Because of this large-scale devastation, such nuclear explosive devices have never again been used in a war. 

It can be seen that the mass numbers on either side of the equation add up to the same number, 238, and that 92 protons are accounted for in the equation s product and reactant sides. This is a balanced nuclear equation. Actually, some mass is converted into energy, but the amount of mass is very small. From Albert Einstein s equation, E = me2, very little mass, m, is needed to produce a tremendous amount of energy, E, because c is the speed of light, 3 x 108 m/sec. This energy was evidenced when an atomic bomb was exploded over Hiroshima, Japan, during World War II. The fuel for that bomb was uranium-235. 

The first atomic bomb was tested at an isolated desert location in New Mexico on July 16,1945. President Truman then issued an ultimatum to Japan that a powerful new weapon could soon be used against them. On August 8, a single atomic bomb destroyed the city of Hiroshima with over 80,000 casualties. On August 11, a second bomb was dropped on Nagasaki with a similar result. The Japanese leaders surrendered three days later. 

For obvious reasons, an atomic bomb is never assembled with the critical mass already present. Instead, the critical mass is formed by using a conventional explosive, such as TNT, to force the fissionable sections together, as shown in Figure 23.9. Neutrons from a source at the center of the device trigger the nuclear chain reaction. Uranium-235 was the fissionable material in the bomb dropped on Hiroshima, Japan, on August 6, 1945. Plutonium-239 was used in the bomb exploded over Nagasaki three days later. The fission reactions generated were similar in these two cases, as was the extent of the destruction. 

On August 6, 1945, after Japan refused to surrender nnconditionally, the first atomic bomb, named Little Boy, a U-based bomb, was dropped over Hiroshima, Japan. Three days later, Fat Man, a plutonium-based weapon, was dropped on Nagasaki. 

In July 1945, tl first such atomic bomb or A-bomb (moib properly called a iission bomb) was e loded in Alamogordo, New Mexico. By the next month, two more bombs were manufactured and were e q>loded over Hiroshima and Nagasaki in Japan, ending World War n. 

Atomic bomb (J. Robert Oppenheimer) Oppenheimer, the scientific leader of the Manhattan Project, heads the team that builds the atomic bomb. On the side of military use of the bomb to end World War II quickly, Oppenheimer saw this come to pass on August 6, 1945, when the bomb was dropped over Hiroshima, Japan, killing and maiming 150,000 people a similar number of casualties ensued in Nagasaki on August 9, when the second bomb was dropped. Japan surrendered on August 14. 

TNT has become such a standard, particularly in military uses, that the destructive power of other explosives, especially in bombs, is often compared to that of an equivalent of TNT. For example, the first atomic bomb—detonated on July 16, 1945, in New Mexico—had the equivalent power of 19,000 tons of TNT. The device exploded over Hiroshima, Japan, which killed more than 140,000 people, had the power of 13,000 tons of TNT. Although these numbers appear huge, comparison with the hydrogen bomb—with the destructive equivalent of 10 million tons of TNT—dwarfs... 

Their work led to the explosion of the first atomic bomb in the New Mexico desert at 5 30 a.m. on July 16,1945. Less than a month later (August 6,1945), the world learned of this new weapon when another bomb was exploded over Hiroshima. This bomb killed 70,000 people and completely devastated an area of 10 square kilometers. Three days later, Nagasaki and its inhabitants met a similar fate. On August 14, Japan surrendered, and World War II was over. 

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