In this chapter, we will understand about different branches of physics. These branches are studied within the scope of physics. We can define the subject physics as:
“The branch of science which deals with the study of matter, and energy, and their interaction between them is called physics“. The word “physics” comes from a Greek word “Fusis”, meaning “knowledge of nature”. It tries to explain and analyze the natural phenomena of the universe by observing and experimenting. For example, physics explains why the sky is blue, why rainbows have colors, etc.
The concepts of physics are very important and play a very important role in the daily life of every living organism. With the help of physics, we can understand a lot of concepts properly. There are some theories which have been proved with the help of physics and its different sub-branches or fields. When we come to the concepts of physics, there are several different branches or fields of it.
In the modern days, all the branches of physics are growing extremely well along with the continuous advance of science and technology. To understand the concepts of physics, it is also important to study of all the branches of physics. So, let’s understand in detail about the physics’s branches.
Table of Contents
Physics and Its Branches or Fields
The amount of concepts available in physics is so huge that, as a matter of convenience, it has been divided into 13 branches. They are as:
- Classical physics
- Modern physics
- Nuclear physics
- Atomic physics
- Geophysics
- Biophysics
- Mechanics
- Acoustics
- Optics
- Thermodynamics
- Astrophysics
- Electromagnetism
- Relativity
All these 13 sub-branches or fields of physics are extremely crucial and provides a vital information for a variety of concepts.
Let’s understand about each branch of physics one by one in brief.
Classical Physics:
The branch of physics which deals with the study of prior to 1890 is called classical physics. Under the classical physics, physicists studied about mechanics, gravitation, heat, sound, light, electricity, and magnetism. The law of motion and gravitation given by Newton had offered a solid foundation of mechanics to the impressive height.
The four laws of thermodynamics and kinetic theory of matter had provided a satisfying explanation about energy conservation and the direction of heat flow. James Clerk Maxwell gave the theory of electromagnetic radiation and described all electrical, magnetic, and optical phenomena. Classical physics cannot work with microscopic particles (e.g. atoms) or objects travelling at very high speed. Therefore, modern physics comes into the existence.
Modern Physics:
The branch of physics which deals with the study of after 1890 is called modern physics. This sub-branch deals with the study of quantum mechanics, relativity, atoms, nuclei, elementary particles like electron, proton, and condensed matter. After 1890, there had been tremendous progresses in physics, which gave birth the several new concepts. For instance, Roentgen discovered X-rays in 1895. A few weeks later, Henry discovered the radioactivity.
In the year 1897, a professor of physics at the University of Cambridge in England, J. J. Thomson discovered the first subatomic particle called electron. In 1901, Max Planck proposed the quantum theory. Albert Einstein proposed a special theory of relativity in 1905, which gave a new concept to atomic and nuclear physics. In short, the discovery of new theory in the modern physics, after 1890, provided several new concepts to the entire physics.
Nuclear Physics:
The branch of physics that is related to with the constituents, structure, behavior and interactions of atomic nuclei is called nuclear physics. This branch of physics differs from the atomic physics. It is one of the most recently developed branches of physics. It also plays an important role in the branches of astrophysics and cosmology.
Atomic Physics:
The branch of physics which deals with the study of the composition of the atom apart from the nucleus is called atomic physics. It deals with the study of atomic structure and the interaction between atoms. Atomic physics is mainly concerned with studying and understanding the behavior, interactions, and properties of electrons in the shells around the nucleus.
Geophysics:
Geophysics simply refers to the physics of earth. It is the branch of earth science that use the principles of physics to study the physical properties of earth and the natural process, that have determined and continue to govern its evolution. Geophysics studies about how does earth works, what is its composition, how has it changes, etc. It studies of electrical, magnetic, gravitational fields, and propagation of seismic waves by quantitative physical methods.
Biophysics:
Biophysics is a branch of science (somewhere between the biology and physics) that deals with the study of biological phenomena using the principles and techniques of physics. It studies the biological structures and processes by applying the theories and mathematics methods of physics. It includes all scales of biological organization, from molecular to organismic and populations. In 1892, Karl Pearson originally developed the term biophysics.
In biophysics, it has been a tedious subject in understanding the mechanics of how molecules of life are made, how different parts of bodies, such as the brain, immune system, and other parts of our body work. Scientists from many areas, including math, chemistry, physics, engineering, pharmacology, and materials sciences, apply their skills to explore and develop new instruments for understanding how biology or all life works.
Mechanics:
The branch of physics that deals with the study of the motion of an object without or with the reference of force is called mechanics. In mechanics, we mainly study the action of different forces and their effects on an object at rest or in motion. Mechanics have further divided into sub-branches. They are:
- Classical mechanics
- Quantum mechanics
Classical Mechanics:
Classical mechanics is the branch of physics that deals with laws of forces and objects moving at speeds small compared with the speed of light. It mainly deals with inertia, motion, force, and energy.
Quantum Mechanics:
Quantum mechanics is the branch of physics that deals with the behaviour of the microscopic particles, like neutrons, protons, and electrons. It touches every aspect of modern physics and most of the classical physics. It gives the satisfactory explanation of the most of the phenomena in modern life.
Acoustics:
Acoustics is the branch of physics that deals with the study of sound and its production, transmission, and effects. It mainly deals with the sound waves or mechanical waves in gases, liquids, and solids. This branch studies and focuses on the production, transmission, control, reception, and effects of sound. It also deals with the study of concepts like vibration, sound, ultrasound, and infrasound. A scientist who works in the subject area of acoustics is an acoustician, while someone working in the discipline of acoustics technology is an acoustical engineer.
Optics:
The branch of physics that deals with the study of the behaviour, propagation, and properties of light is called optics. It also states the behaviour of infrared light, visible light, and ultraviolet. There are two branches come under the optics physics: physical optics and geometrical optics.
The physical optics concerns with nature of light and other properties, while geometrical optics focuses on the interactions of light with lenses, mirrors, and other devices, such as lasers, fibers, sensors, etc. Optics has many usages in the field of information technology, telecommunications, health care, biotechnology, sensing, lighting, energy, and manufacturing.
Thermodynamics:
Thermodynamics is the branch of science that deals with the study of energy and its transformation. It mainly deals with heat and its interaction with matter. It also studies the relationship between heat and work, and properties of systems in equilibrium. The four laws, namely zeroth, first, second, and third laws of thermodynamics are the principles of thermodynamics.
Astrophysics:
This branch of science deals with the study of astronomical objects and phenomena by using methods and principles of physics and chemistry. Since it is a very broad subject, astrophysicists apply concepts and principles from many disciplines of physics, including classical mechanics, electromagnetism, statistical mechanics, thermodynamics, quantum mechanics, relativity, nuclear and particle physics, and atomic physics.
Electromagnetism:
This branch of physics deals with the study of electricity, magnetism, and electromagnetic radiation. In electromagnetism, we study about electromagnetic force like electric fields, light, magnetic fields, etc.
Relativity:
This branch of physics deals with the theory that was discovered by a great scientist Albert Einstein in 1905. This theory has changed our perceptions of space and time and of mass and energy. The theory of relativity establishes a relation between space and time. It gives two postulates:
- The laws of physics are the identical in all uniformly moving frames of reference.
- The speed of light is the same for all observers, even they are moving with respect to one another.
In this tutorial, we have explained different branches of physics in brief. Hope that you will have understood the basic points of each branch of physics and enjoyed it.
