What is an atomic bomb?

Answer 1

An atomic bomb is any bomb which obtains its destructive energy from the excess binding energy of atomic nuclei. The term is most commonly applied to bombs that release the excess binding energy of heavy atoms by fissioning them to form lighter atoms, but can equally correctly be applied to bombs that release the excess binding energy of light atoms by fusing them to form heavier atoms (however such bombs are most commonly called hydrogen bombs).

The fine details of this are somewhat blurred as most modern nuclear weapons use some combination of both fission and fusion, regardless of what they are called (e.g. dial-a-yield tritium gas fusion boosted atomic bombs, conventionally built hydrogen fusion bombs usually get more than 90% of their yield from fast fission of their depleted uranium tamper) to optimize their characteristics.

Answer 2

There are two basic types of nuclear weapons: those that get most of their energy from nuclear fissionreactions alone, and those that use fission reactions to begin nuclear fusion reactions that produce a huge explosive output.

The fission type bombs are called atomic bombs or atom bombs (abbreviated as A-bombs).

In fission weapons, a mass enriched uranium or plutonium is brought to a supercritical mass (the
amount of material needed to start a nuclear chain reaction) either by shooting one piece
of sub-critical material into another (the "gun" method) or by squeezing together sub-critical spheres
by using chemical explosives (the "implosion" method).

The fission way can be only be used if the fissile material is plutonium.


A major challenge in all nuclear weapon designs is to make sure that a very large fraction of the fuel is consumed before the weapon destroys itself.

The amount of energy released by fission bombs can range from the equivalent of just under
a ton of TNT, to upwards of 500,000 tons (500 kilotons) of TNT.

All fission reactions produce radioactive remains. Many fission products are either highly radioactive (but short-lived) or moderately radioactive (but long-lived). That makes them a form of radioactive contamination if not fully contained.

Fission products are the principal radioactive component of nuclear fallout.

The most commonly used fissile materials for nuclear weapons have been uranium-235 and plutonium-239. Less commonly used has been uranium-233. Neptunium-237 and some isotopes of americium may be usable.

Answer 3

An atomic bomb is a nuclear weapon which obtains its destructive energy from nuclear fission.