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What is an atomic bomb?


When an atom - such as of plutonium or uranium – strikes a neutron, the atomic nucleus is split into two fragments (nuclear fission) and neutrons split off from the nucleus, releasing enormous energy. The atomic bomb is a means of using this energy as a weapon; weapons based on the above mechanism are called “nuclear weapons.”

When an atomic bomb explodes, it creates a fireball and emits enormous heat rays and radiation. The heated air expands at a tremendous pace, producing a violent blast. The complex interrelations of heat rays, radiation and blast amplify the damage.

<A-bomb dropped on Nagasaki>
・Material used: Plutonium
・Explosive force: Equivalent to 21,000 tons of TNT
・Size: Approx.3.25 m in length, approx.1.52 m in diameter
・Weight: Approx. 4.5 tons
Nicknamed “Fatman” because of its shape and size.

  Theory of the Atomic Bomb
  How the Explosion of the Nagasaki-type Atomic Bomb Occurs

Nagasaki Atomic Bomb Museum
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