Ever since the dawn of time man has found new ways of killing
each other. The most destructive way of killing people known to man
would have to be the atomic bomb. The reason why the atomic bomb is so
destructive is that when it is detonated, it has more than one effect.
The effects of the atomic bomb are so great that Nikita Khrushchev
said that the survivors would envy the dead (International Physicians
for the Prevention of Nuclear War, 1982). These devastating physical
effects come from the atomic bombs blast, the atomic bombs thermal
radiation, and the atomic bombs nuclear radiation.
An atomic bomb is any weapon that gets its destructive power
from an atom. This power comes when the matter inside of the atoms is
transformed into energy. The process by which this is done is known
as fission. The only two atoms suitable for fissioning are the
uranium isotope U-235 and the plutonium isotope Pu-239 (Outlaw
Labs). Fission occurs when a neutron, a subatomic particle with no
electrical charge, strikes the nucleus of one of these isotopes and
causes it to split apart. When the nucleus is split, a large amount
of energy is produced, and more free neutrons are also released.
These neutrons then in turn strike other atoms, which causes more
energy to be released. If this process is repeated, a self-sustaining
chain reaction will occur, and it is this chain reaction that causes
the atomic bomb to have its destructive power (World Book, 1990).
This chain reaction can be attained in two different ways.
The first type of atomic bomb ever used was a gun-type. In
this type two subcritical pieces of U-235 are placed in a device
similar to the barrel of an artillery shell. One piece is placed at
one end of the barrel and will remain there at rest.
subcritical mass is placed at the other end of the barrel. A
conventional explosive is packed behind the second subcritical mass.
When the fuse is triggered, a conventional explosion causes the second
subcritical mass to be propelled at a high velocity into the first
subcritical mass. The resulting combination causes the two
subcritical masses to become a supercritical mass. When this
supercritical mass is obtained, a rapid self-sustained chain reaction
is caused (World Book, 1990). This type of atomic bomb was used on
Hiroshima, and given the nickname Little Boy after Franklin D.
Roosevelt (Outlaw Labs).
The second type of atomic bomb is an implosion bomb. In this
type a subcritical mass, which is in the shape of a ball, is placed in
the center of the weapon. This subcritical mass is surrounded in a
spherical arrangement of conventional explosives. When the fuse is
triggered all of the conventional explosives explode at the same time.
This causes the subcritical mass to be compressed into a smaller
volume, thus creating a supercritical mass to be formed.
supercritical mass is obtained, a self-sustained chain reaction takes
place and causes the atomic explosion (World Book, 1990). This
type of stomic bomb was used on Nagasaki, and given the nickname Fat
Man after Winston Churchill (Outlaw Labs).
The blast from an atomic bombs explosion will last for only
one-half to one second, but in this amount of time a great deal of
damage is done (Physicians and Scientists on Nuclear War, 1981). A
fireball is created by the blast, which consists mainly of dust and
gasses. The dust produced in this fireball has no substantial effect
on humans or their environment. However, as the gasses expand a blast
wave is produced.
As this blast wave moves, it creates static
overpressure. This static overpressure then in turn creates dynamic
pressure. The static overpressure has the power to crush buildings.
The dynamic pressure creates winds, which have the power to blow down
trees (International Physicians for the Prevention of Nuclear War,
1982). The blast pressure and fireball together only last for
approximately eleven seconds, but because it contaitns fifty percent
of the atomic bombs latent energy a great deal of destruction occures
(The Committee for the Compilation of Materials on Damage Caused by
the Atomic Bombs in Hiroshima and Nagasaki, 1981).