Why is the atom bomb so destructive? The weapon derives its explosive force from the release of atomic energy through the fission (splitting) of heavy nuclei.
The first atom bomb was produced by the United States and successfully tested on July 16, 1945.
Practical fissionable nuclei for atom bombs are the isotopes uranium 235 and plutonium 239 which are capable of undergoing a chain reaction.
If the mass of the fissionable material exceeds the critical mass, the chain reaction multiplies rapidly into an uncontrollable release of energy.
An atomic bomb explosion produces, in addition to the shock wave accompanying any explosion, intense neutron and gamma radiation, both of which are damaging to living tissue.
The area surrounding the site of the atomic explosion becomes contaminated with radioactive fission products.