Question

Hydrogen bomb is based on the principle of (a) artificial radioactivity (b) nuclear fission (c) nuclear fusion (d) natural radioactivity

Short answer

c) nuclear fusion

Step-by-step solution

Understanding the Problem

We need to identify the principle behind the working of a hydrogen bomb from the given options.

Identify Relevant Principles

Among the principles given, 'nuclear fission' involves splitting of atomic nuclei, 'nuclear fusion' involves the combination of smaller nuclei to form a larger nucleus, 'artificial radioactivity' is radioactivity induced by human intervention, and 'natural radioactivity' is spontaneous emission of radiation by unstable atomic nuclei in nature.

Clarifying Concepts of Nuclear Reactions

A hydrogen bomb works through nuclear fusion, where light nuclei (like isotopes of hydrogen) fuse together at extremely high temperatures to form a heavier nucleus, releasing tremendous energy.

Selecting the Correct Principle

Given the definition and mechanism of a hydrogen bomb, the principle that best fits its operation is nuclear fusion.

Key concepts

Nuclear Fusion

In the core of the hydrogen bomb lies the awe-inspiring process of nuclear fusion. This phenomenon occurs when two smaller atomic nuclei unite to form a larger nucleus. Typically, the nuclei involved are isotopes of hydrogen, such as deuterium and tritium.

During fusion, an enormous amount of energy is released, which significantly exceeds the energy released by nuclear fission. This is why nuclear fusion is considered the driving force behind the immense power of the hydrogen bomb.

The process requires extremely high temperatures and pressures, akin to the conditions inside the sun, where hydrogen fusion naturally occurs. This need for intense environmental conditions makes it a challenge to harness for other peaceful applications on Earth.

Nuclear Fission

Nuclear fission, while not the principle behind the hydrogen bomb, is a fascinating and equally powerful nuclear reaction. It involves the splitting of a large atomic nucleus into two smaller nuclei, accompanied by the release of a large amount of energy.

This process is the cornerstone of atomic bombs and nuclear reactors. Unlike fusion, fission can occur under more easily achievable conditions, which is why it finds use in power generation across the globe.

• The reaction commonly uses elements like uranium-235 or plutonium-239.
• Fission releases not only energy but also neutrons, which can perpetuate the reaction.
• This chain reaction characteristic is pivotal for controlled energy release in nuclear reactors.

Radioactivity

Radioactivity is a natural or induced process by which unstable atomic nuclei lose energy by emitting radiation. This phenomenon can occur either spontaneously or through human intervention in artificial radioactivity.

The substances emit particles such as alpha particles, beta particles, and gamma rays, each carrying different levels of energy and penetration abilities.

• Alpha particles consist of 2 protons and 2 neutrons; they have low penetration power but can be extremely harmful when ingested.
• Beta particles are fast-moving electrons or positrons, with greater penetration than alpha particles.
• Gamma rays are high-energy electromagnetic waves, capable of passing through most materials, necessitating thick shielding for protection.

Understanding radioactivity helps in grasping the principles of both nuclear fission and fusion, as it is often a by-product of these reactions.

Nuclear Reactions

Nuclear reactions are processes where the nuclei of atoms change, releasing or absorbing vast amounts of energy. These reactions can be categorized based on the change they invoke in the nucleus, such as fusion or fission.

Key characteristics of nuclear reactions include:

• The involvement of atomic particles such as neutrons, protons, and other subatomic elements.
• Significant energy changes, often transforming mass into energy as explained by Einstein's equation, \( E = mc^2 \).
• The potential to produce radioactivity as a result.

Nuclear reactions are foundational to the principles of nuclear physics and have profound implications in energy generation, medicine, and defense capabilities, with fusion being the primary reaction utilized in hydrogen bombs.