Nuclear Fusion and Fission

When we all are looking at the sky and view the stars, everything we see is shining because of distant nuclear fusion. We all are familiar with this word “Nuclear fusion”. Fusion basically means blending, so nuclear fusion is blending of nuclei?? It is true in some manner but not completely.

Nuclear fusion is a nuclear process in which two nuclei combine to form a heavy nuclei but now a question arise we know nuclei are positively charged and according to law of electrostatics, they will repel each other, then how will they combine?? “

Strong Nuclear Force” is the strongest fundamental force known in nature we all know that, so we only have to bring the two nuclei to a certain distance so then strong nuclear force can act upon it. How will we bring them??We have to do some work; do we use our hands to bring them to a certain distance? Unfortunately, that’s not possible as they are very small So what we do?

We simply provide them heat, temperature is increased, hence kinetic energy is increased according to kinetic theory of gases K.E. = 3/2KT. By kinetic energy theory, we know that 3×10^9 K temperature is required. Hence, kinetic energy required is 400keV. Condition of high temperature and pressure are required. Protons are link particles in this process. This temperature of 10^9 K cannot be achieved on Earth, only be maintained in stars like the Sun.

We know that before exploding hydrogen bomb, atom bomb is exploded. What’s the role of this atom bomb? This atom bomb release large amount of energy that increase the temperature and hence provide the required temperature for hydrogen bomb. This is the principle of working of hydrogen bomb.

We have heard nuclear fusion takes place in the Sun. Why not Nuclear Fission??

This is because Sun is composed of 90% hydrogen and helium gas , Only 10% of other  elements and organic complexes are present. Scientists are still finding out that how organic complexes are present here?

For fusion, heavy elements are required which are not present here , therefore Sun gives tremendous amount of energy by fusing hydrogen to helium.

The average temperature of Sun’s core is about 1.5× 10^7 K which is definitely not sufficient for fusion of hydrogen. If we use 1.5×10^7 K, kinetic energy is 2 KeV. How Nuclear fusion will take place??

Twist is that this is average kinetic energy. This was solved by MAXWELL-BOLTZMANN LAW that states that if we took a closed box and gas is filled in it, every atom of gas has different energy level, some greater than 2 keV, some equal to 2keV, some less than 2 keV, hence nuclear fusion is possible.

Nuclear fusion is an exothermic process, once fusion starts, no external heating is required, and temperature needs not to be maintained. It is self-sufficient.

Nuclear fusion is more energy efficient than nuclear fission as 1 unit mass of uranium gives 0.85 MeV while 1 unit mass of hydrogen gives 6 .7 MeV.

 It is ended by famous saying of Stephen Hawking, “I would like nuclear fusion to become a practical power source. It would provide an inexhaustible supply of energy without pollution or global warming”.