It seems there is some confusion over these different types of bombs, the Atom, Hydrogen and Nuclear Bomb.
Both the Atom and the Hydrogen bomb are in fact Nuclear Bombs, as their explosive energy comes from the nucleus of the atom, therefore a nuclear explosion.
Atom Bomb
The first A-bomb, (Atom Bomb) is a fission bomb, and had the power of about 20,000 tons of TNT.
Hydrogen Bomb
The H-bomb (Hydrogen bomb) is a fusion bomb and is normally called a thermonuclear bomb.
The explosive energy comes from the fusion reaction between isotopes of hydrogen
The largest H Bomb so far has the power of about 50,000,000 tons of TNT. This is about 2,500 times the power of the first A Bomb.
The H-Bomb uses an Atomic explosion as its detonator.
The above, Little Boy and Fat Man, are the only TWO bombs of these types, that have EVER been used in action.
- Little Boy used about 800 milligrams of uranium-235 in the bomb and exploded with the power of about 16,000 tons of TNT.
- Fat Man used plutonium-239, and exploded with the power of about 21,000 tons of TNT.
At the peak of the Cold War it is estimated that there were about 70-80,000 Hydrogen Bombs available for use.
This has been trimmed down to the region of 30,000 following nuclear disarmament policies.
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