Block 2 Physical Science

1. Nuclear Fusion
By Kayla Jameson and Lance Hixson

2. Definition Of Nuclear Fusion
● Nuclear fusion is a nuclear
reaction in which two light
nuclei (such as hydrogen)
combine to form a heavier
nuclei (such as helium).
The process releases
excess binding energy from
the reaction, based upon
the binding energies of the
atoms involved in the
process.
● Nuclear fusion is the
energy source of the
future. It is what
provides the sun and
the stars with the
energy to shine
continuously for
billions of years.

3. Renewable and Non-renewable

4. How Does It Work
The essential precondition required for a nuclear fusion to
take place is that each of the nucleus should be highly
energized, to overcome the very strong mutual repulsion of
their positively charged nuclei. This is achieved by raising
the temperature of the fuel material to an extremely high
point. To attain such a high temperature, in a short span of
time, the fuel is enveloped with uranium, and is allowed to
undergo fission (a nuclear reaction in which heavy nucleus
of uranium splits into smaller nuclei and release a lot of
energy) chain reaction. Thus, the heat generated from the
fission reaction of uranium, energizes the hydrogen atoms
and forces them to undergo fusion and liberate energy in
large magnitude.

5. Uses Of Nuclear Fusion
The source of energy in the stars
including the sun, is believed to be
due to the conversion of hydrogen
into helium by the fusion process.
Intensive research to produce
electricity from nuclear fusion, has
been going on for many years. Due
to some technical and scientific
difficulties, the power generated
has not been put into practical use
so far. Once we overcome these
obstacles, electric power
generation will be much cheaper
and power crisis would be resolved
once and for all. If a fusion reaction
is carried out in an uncontrolled
manner, then it will cause a
thermonuclear explosion similar to
exploding a hydrogen bomb.

6. History Of Nuclear Fusion
Australian physicist Mark
Oliphant gave an
experimental
demonstration of nuclear
fusion, for the first time in
1932. Later, the stages of
the cycle of nuclear
fusion that take place in
stars was explained by
famous physicist Hans
Bethe. The exploration
for the possible uses of
nuclear fusion for military
purposes began in early
1940s. On the other
hand, the research work
for utilizing fusion for
civilian use started in the
1950s.

7. Advantages and Disadvantages
The major advantages of nuclear fusion are easy availability of fuel and
minimum environmental pollution. The fuels used for nuclear fusion are
mainly deuterium and tritium. Deuterium( a heavy isotope of hydrogen)
can be obtained from the surface waters on Earth. Tritium is produced
from lithium. Lithium is available in abundance on the land deposits and
seawater. As both the fuels are, almost inexhaustible, the probability of
having a fuel crisis is nil for thousands of years to come.
As fossil fuels are not being used, there is no possibility of release of
chemical combustion products. Likewise, no fusion products are formed
and so handling and disposal problems do not arise. So far, scientists
have not been able to fully control the fusion processes over a prolonged
period of time. So, it cannot be used for practical purposes.
The energy released in a nuclear fusion, is much higher than any
chemical reactions. It is possible to use this energy in various ways in the
future. But care should be taken that it is sustained in a controlled
manner and used only for peaceful purposes