Neutrons and protons are collectively called nucleons are live in nucleus. We know that, there is repulsive force between two protons.Why does they stay together in nucleus? There must be a dominant force than repulsive electrostatic force which is responsible to bind two or more protons in nucleus together. This dominant force is called strong nuclear force. The energy associated with this force is nuclear binding energy.
Definition of nuclear binding energy- The energy binds nuclear particle together is called nuclear binding energy.
Or
The energy required to separate two nucleons is called binding energy.
Nuclear fission:
Heavynucleus are unstable in nature like bigger water drop. Minimumbinding energy requires to separate this nuclear particle from each other.
A heavy nucleus split up into two or more than twolight stable nuclei,such reaction is called as nuclear fission reaction.
When slow moving neutron collides on such heavy nucleus thenthat nucleus split up into small nuclei, the energy released in such reaction is about 2 MeV.
235U+ 1n ⇒ 144Ba + 89Kr + 3 1n
Where,
U – uranium and mass number of Uranium is 235.
n – a neutron.
Ba – Barium and mass number of Barium is 144.
Kr –Krypton and mass number of krypton is 89.
A neutron collides on heavy nucleus of uranium then it split up into smaller nuclei like barium and Krypton.In such reaction huge energyis released. What is the source of this energy?Mass of Uranium is greater than mass of Barium and Krypton. This mass is converted into energy. According to Einstein’s mass energy relation,
E = ∆mc2
Where,
E- Energy.
∆m – mass difference between mass of parent nucleus Uranium and daughter nuclei Barium and Krypton.
c – velocity of light and it’s value is 3 × 108 m/s.
The value of mass is small but when it multiplied with square of velocity of light it gives greater value. Such huge energy will release in nuclear reaction.
One neutron collides on heavy nucleus like Uranium then it split up that nuclear into small nuclei with other three neutrons. These three generated neutrons again collides withuranium nucleus and produce three neutronseach. So number of neutrons are multiplied like this. The multiplication in nuclear reaction is as shown in figure
If we can not control this chain reactions then it becomes nuclear bomb.
The energy generated in such reaction is use for generation of steam. The energy in this steam rotates dynamo and it will produce electric current. Nuclear reactors are based on the principle of nuclear fusion reaction. Nuclear reactors in India
- Tarapur (Maharashtra)
- Rana Pratap Sagar (Rajasthan)
- Kalkapakkam (Tamil Nadu)
- Narora (Uttar Pradesh)
- Kakrapar (Gujarat)
- Kaiga (Karnataka)
Nuclear fusion:
Sun is a universal source of energy. What is the source of this huge energy? Sun continuously emit energy in the form of electromagnetic radiations because some nuclear reactions takes place on the surface of sun. That nuclear reactions are nuclear fusion reactions. As we discussed that, heavy nucleus is instable in nature similarly light nucleus is also unstable. Stability of nucleus is explained on the basis of liquid water drop. Small or more heavy water drop are not stable. For stability small water drop combine each other and form a stable one. Similarly small nucleus fuse together and form a stable nucleus. Such nuclear reactions are called as nuclear fusion reactions.
Definition: Two or more light nuclei fuse each other and form a new stable nucleus, this nuclear reaction is called nuclear fusion reaction.
2H + 2H⇒3He + 1n
Where
2H – isotope of hydrogen atom.
He- helium
n- neutron
Two light nucleus of hydrogen fuse tougher and form a stable nucleus of helium. This reaction also produce a neutron. Neutron has so many applications in the field of research and medical.
Nuclear fusion reactions produces large energy in the form of heat. Temperature of core of sun is about 60000 c. The source of this temperature is also nuclear fusion reactions.
Advantages of nuclear energy:
- Nuclear energy can be obtained in large amount. One kilogram of uranium can produces powerupto 2 × 109
- Nuclear energy is economically cheap. It require radioactive fuel like uranium in small amount.
- It does not produce smoke in atmosphere like burning of coal.
Disadvantages:
- Nuclear energy is non renewable type of energy.
- It produces to much nuclear harmful waste of radioactive materials.
- If we do not able to control nuclear reaction, then it destroy all.
- Nuclear reactions requires lots of water as a coolant.
Answer the following questions
- Write and explain any nuclear fusion and fission reaction.
- Which material is a used as a source in nuclear reactor?
- Who is the father of India’s nuclear energy program?
- List out the nuclear reactors in India.
- What is the source of energy of sun?