Question

Atom bomb is based on the principle of (a) nuclear fusion (b) nuclear fission (c) nuclear transformation (d) carbon dating

Short answer

Nuclear fission (b).

Step-by-step solution

Understanding the Context

The question asks for the principle on which an atom bomb is based. We know that atom bombs are explosive devices that involve nuclear reactions.

Analyzing the Options

Let's look at the options given: (a) Nuclear fusion - This is a process where two light atomic nuclei combine to form a heavier nucleus, releasing energy in the process. This is the principle behind the energy produced in the sun. (b) Nuclear fission - This process involves the splitting of a heavy nucleus into lighter nuclei, which also releases energy. This is the principle typically used in nuclear reactors and atomic bombs. (c) Nuclear transformation - This is a more general term and doesn't specifically point to a single reaction being used for bombs. (d) Carbon dating - This is a radiometric dating method and is not relevant to the operation of an atomic bomb.

Identifying the Correct Principle

By analyzing the options, we can see that nuclear fission (option b) is the process directly related to the functioning of an atom bomb. This process releases a large amount of energy from the splitting of atomic nuclei, which creates the explosive power of an atomic bomb.

Key concepts

Nuclear Fusion

Nuclear fusion is an incredible process seen in the very heart of stars like our sun. It involves the merging of two light atomic nuclei into a single heavier nucleus. This fusion releases a significant amount of energy, which is why the sun shines so brightly. The equation generally representing fusion is:\[ \text{^2_1H + ^2_1H} \rightarrow \text{^4_2He + energy} \]Here, two hydrogen nuclei (often isotopes deuterium or tritium) combine to produce a helium nucleus, leading to a mass that is slightly less than the original deuterium nuclei. This mass difference is released as energy based on Einstein’s famous equation, \(E=mc^2\).
Nuclear fusion holds promise as a potential energy source because it produces large amounts of energy and only minimal radioactive waste. However, achieving fusion on Earth involves extremely high temperatures and pressures, similar to those found in stars, making it a challenge to sustain and control. Though not used in atomic bombs, fusion is a basis for hydrogen bombs, which are much more powerful and advanced than fission-based atom bombs.

Atomic Bomb

The atomic bomb is one of the greatest displays of the destructive potential of nuclear fission. The principle behind an atomic bomb is the explosive release of energy from splitting atomic nuclei. This process also releases additional neutrons that initiate a chain reaction, causing further fission in nearby nuclei. In an atomic bomb, this chain reaction occurs in a fraction of a second, unleashing massive energy.
The bombs dropped on Hiroshima and Nagasaki in 1945 used nuclear fission to create explosions equivalent to thousands of tons of TNT. They utilized uranium-235 or plutonium-239, isotopes that are fissionable and that reliably maintain a chain reaction when neutrons bombard them.

• Uranium or Plutonium nucleus absorbs a neutron.
• It becomes unstable and splits into two smaller nuclei.
• Releases multiple neutrons and a huge amount of energy.

This results in an explosive release of energy with devastating effects. The atomic bomb, while a product of advanced science, remains a powerful reminder of the potential consequences of nuclear experiments.

Nuclear Reactions

Nuclear reactions involve changes in an atom's nucleus and are responsible for generating immense amounts of energy. They can either be fusion or fission.

Types of Nuclear Reactions:

• Nuclear Fusion: Two light nuclei combine to form a heavier nucleus with energy released. This is the reaction that powers stars.
• Nuclear Fission: Causes a heavy nucleus to split into two lighter nuclei, releasing energy. Used in nuclear reactors and atomic bombs.
• Radiative Capture: A nucleus captures a neutron and emits gamma radiation.

Both nuclear fission and fusion release energy due to the mass-energy equivalence principle, \(E=mc^2\).

In fission, the nuclei split into smaller fragments, while in fusion, light nuclei combine. They both produce energy, but their processes are opposite. In daily life, nuclear reactions power nuclear plants and provide medical isotopes for treatments, showcasing their dual-use nature. Although these reactions can solve energy issues, safety is paramount due to potential devastating consequences of meltdown or misuse.