Question

Define: Fusion

Answer 1

Hint :Generally fusion refers to the process of combining elements into one bigger form. The process involves change of properties from the ones which react. They cannot retain their own properties after a fusion reaction. Fusion is the combining of objects which may result in evolution of energy. Fusions mainly occur on the sun surface.

Complete Step By Step Answer:
Fusion in terms of nuclear process is nuclear fusion. In nuclear fission nuclei of lower atomic mass atoms strike and combine with each other to form one or many heavier nuclei. The process of nuclear fusion releases a tremendous amount of energy which is very difficult to store. The process will not stop easily.
Fusion occurs on the Sun surface due to which the temperature of the surface of the Sun is around five thousand Kelvin.
In the universe the light energy, heat energy and every other type are obtained by fusion reactions. The process of fusion needs extreme conditions to occur such as high temperature and pressure to overcome the coulomb force between the reactants.
If we could control the energy produced in fusion it will finish all the energy scarcity in the world.
 $ {}_1^2H + {}_1^2H \to {}_2^3He + {}_0^1n + 3.27MeV $
In the above reaction two nuclei of deuterium collide and form a heavy nuclei of helium with release of energy.

Note :
The raw materials for the fusion reaction are present in a very large amount hence the material is economical. The process does not involve evolution of harmful gases and the waste left after the reaction is all very less. Thus nuclear fusion energy is clean and green energy which is the need of the future.