Question

What is nuclear fusion?

Hint:

Fusion requires extremely high temperature (about $10^7$ K) and pressure, which is why it is very hard to achieve on Earth.

Answer 1

Step 1: Definition
Nuclear fusion is a process in which two or more light atomic nuclei combine to form a heavier and more stable nucleus. During this process, a tremendous amount of energy is released.

Step 2: Scientific Explanation
Fusion generally occurs with isotopes of hydrogen, such as Deuterium ($^{2}_{1}H$) and Tritium ($^{3}_{1}H$).
When these nuclei fuse under extremely high temperature and pressure, they form Helium ($^{4}_{2}He$) and release a large amount of energy in the form of light and heat.
Step 3: Fusion Reaction Equation
\[ ^{2}_{1}H + ^{3}_{1}H \longrightarrow ^{4}_{2}He + ^{1}_{0}n + \text{Energy} \]
Step 4: Where Does It Occur?
In Stars: The Sun and other stars shine due to nuclear fusion reactions occurring at their core.
In Hydrogen Bombs: Human technology has used uncontrolled fusion for weapons.
Step 5: Importance
Fusion produces much more energy than nuclear fission.
It is considered the ultimate source of renewable energy if controlled fusion can be achieved on Earth.
Final Answer:
Nuclear fusion is the process of combining lighter nuclei (like hydrogen isotopes) to form a heavier nucleus (helium), releasing a huge amount of energy.