Page 106 - The Miracle in the Atom

Neutron

Uranium 235

such an enormous force
fit in such a small place?
This is such a force that it has
been discovered after years of rese-
arch conducted by thousands of people.
When it is not interfered with, it does not do
any harm to anyone, yet, with the intervention
of man, it may at any time become a force killing
millions.
Two technical processes called "fission" and "fusion"
release this extraordinary force in the nucleus of the atom,
which may endanger the lives of millions of people. The reaction
known as fission is a nuclear reaction in which an atomic nucleus splits
into fragments, and the reaction called fusion is the bringing together of
two nuclei by a great force. In either reaction, a tremendous amount of ener-
gy is released.

Fission
Fission is a nuclear reaction in which the atomic nucleus, which is held
together by the strongest force in the universe, the "Strong Nuclear Force",
splits into fragments. The main material used in fission experiments is "ura-
nium" because the uranium atom is one of the heaviest. In other words, the-
re are plenty of protons and neutrons in its nucleus.
In fission experiments, scientists shot a neutron at the uranium nucleus
at great velocity. They faced a very interesting situation. After the neutron
was absorbed by the uranium's nucleus, the uranium nucleus had become
very unstable. The nucleus' being "unstable" means the formation of a diffe-

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