Among all the fundamental domains of science, Physics is unarguably the most important one. Physics contributes to the technological infrastructure and provides trained personnel needed to take advantage of scientific advances and discoveries. Additionally, physics extends and enhances our understanding of other disciplines, such as the earth, agricultural, chemical, biological, and environmental sciences, plus astrophysics and cosmology – subjects of substantial importance to all peoples of the world. In this post, we will look at the core branches of physics.
Branches of Physics and Definitions
Co-authored by Parunita Gupta
What is Physics?
Physics is a branch of science that deals with the structure of matter and the interactions between the fundamental constituents of the observable universe.
Physics can, at the base, be defined as the science of matter, motion, and energy. Its laws are typically expressed with economy and precision in the language of mathematics.
Objectives of Physics
It studies not only the behavior of objects under the action of given forces but also the nature and origin of gravitational, electromagnetic, and nuclear force fields. Its ultimate objective is the formulation of a few comprehensive principles that bring together and explain all such disparate phenomena.
Related Post: Top Government (Public) Institutes in India for Research in Physics
However, today the field has evolved so much more that it has further developed branches of its own, and that’s exactly what we’re going to list down here.
To start with, physics can broadly be categorized into two main branches. One is classical physics, and the other, modern physics.
Further, these branches divide out into the following sub-branches:
- Mechanical physics / Mechanics
- Magnetism
- Electricity and electronics
- Electromagnetism
- Sound and oscillation
- Acoustics
- Thermodynamics
- Optics
- Geo physics
- Plasma physics
- Nuclear physics
- Astrophysics
Let’s start breaking it down, one at a time!
Branches of Physics
1. Mechanical Physics / Mechanics
One of the most basic and fundamental branches of classical physics, mechanics is concerned with the study of movements and motions of material objects and how these objects are affected by and interact with other different forces.
Mechanics explores the different concepts of physics such as force, matter, and motion and studies its laws, properties, and applications. Quite ironically, this branch of physics further has sub-branches, namely classical mechanics and quantum mechanics.
While classical mechanics focus on the laws of motions and how they affect material objects; on the other hand, quantum mechanics focuses on how these forces mentioned thereof act on the smallest of the particles such as electrons, protons, and neutrons.’
Quantum Physics
Mechanics is one of the sub-fields of Quantum Physics.
Quantum mechanics is the branch of physics needed to deal with submicroscopic objects. Like relativity, quantum mechanics has been shown to be valid—the truth is often stranger than fiction.
Apart from Quantum Physics, Atomic Physics and Molecular Physics are also important subfields.
However, as per a few definitions, Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. Hence, we are not considering Quantum Physics as one of the most popular branches of physics within this article.
2. Magnetism
Magnetism explores the properties of a magnet and how magnetic forces and fields act or react when they interact with other forces or even each other.
It’s no secret to us that magnetic forces act in two directions, i.e., South and North. This is exactly what is studied here, i.e., the forces exerted by magnets when they attract or repel one another.
It also studies how these magnetic fields react when they come in contact with different forces like the gravitational field and electric field, or how magnets are made, to begin with, and how or if they lose their properties over time or not. Its concepts like these make it one of the most interesting branches of physics.
3. Electricity and Electronics
Electricity and electronics are two different branches of physics but very close to each other, hence we decided to put them in the same category.
While electricity refers to the branch of physics which is concerned with the study of properties and movements of electrically charged particles of an object, including on a much deeper level, i.e., of electrons and protons, it also explores the various concepts of electricity such as, resistance, current, AC and DC, and happens to be quite entangled with the branch magnetism, which we are going to discuss next.
On the other hand, Electronics simply refers to the branch of physics where they study applications of electricity and how it works on various appliances and new pieces of technology.
4. Electromagnetism
As mentioned above, magnetism and electricity are quite interrelated with each other, and that is because movements of electrical charges end up creating magnetic fields while manipulation of magnetic fields renders to the production of electricity.
Electromagnetism refers to the study of the magnetic forces and fields that are created via the movements of electrical charges and vice versa.
5. Sound and Oscillation
This is one of the most fundamental branches of physics which studies objects in a state of oscillation or vibration, being in a constate state of motion which may be linear or to &fro.
That being said, when an oscillating object has frequency lying within an audible range, the sound is produced. Different frequencies of oscillating objects produce different vibrations into the air, which may or may not be of the audible range.
This branch studies the various properties of different oscillating objects and how their vibrations and frequencies vary from one another. It also explores the various frequency ranges, their effect on other objects and living beings, etc. It’s quite an interesting topic to study, especially for kids.
6. Acoustics
This branch is quite interrelated with sound and oscillation. However, acoustics aims to explore the concepts of how the mechanical sound waves transmit through different objects and mediums i.e., solids, liquids, and gases.
It studies what effect these vibrations bring on to the medium that it’s traveling through and how the medium as well affects these waves. To be put simply, it focuses on the production, control, transmission, and reception of these sound waves and also their effects.
Acoustics also studies vibrations that belong to the inaudible ranges of frequency, i.e., ultrasounds and infrasound.
7. Thermodynamics
This is a branch of physics that deals with the concept of heat and studies its relation to work and energy. It also studies the way heat is transmitted between objects and from one medium to another and how it affects the medium and the energy itself.
There are several ways in which heat can be transmitted into different mediums, it could be convection, conduction, and radiation, unlike sound which has to otherwise be directly in contact with the medium in order to travel through it via its vibrations.
8. Optics
In this branch of physics, the properties and behavior of light are studied, along with the properties of non-opaque, semi-opaque, and reflective objects and how they interact with light. Even opaque objects are discussed since their colors reflect light.
Just like sound, light too has wavelengths, which categorizes them into visible and non-visible ranges. Hence, the properties of non-visible lights such as ultraviolet and infrared lights are studied as well, along with their properties of radiation. This is also where thermodynamics comes in as well.
9. Geo-physics
This branch of physics is rather a part of natural science since it attempts to study the behavior of geographical bodies and how studies its movements affect different other bodies on the planet.
It studies the physical processes and properties of the earth and the space environment surrounding it. It uses several quantitative (and sometimes qualitative) methods of research for analysis and reaching down to a conclusion.
10. Plasma Physics
Most of us at school have been taught about the 3 states of matter, i.e., solids, liquids, and gasses, however, there also happens to be the fourth state of matter, i.e., plasma. The study which involves the properties and behavior of this fourth state of matter is what is meant by the plasma physics
11. Nuclear Physics
Who knew something so small could have a whole branch of physics dedicated to it?
Nuclear physics refers to the branch of physics which studies the nucleus of an atom, which consists of protons and neutrons. It studies various forces and interactions within the nucleus that holds the whole thing together. The study is limited to such a small thing, and yet is one of the most complex branches of physics.
12. Astrophysics
Astrophysics is an important branch of physics. It is a sub-field within astronomy.
The field of astrophysics applies the laws of physics and chemistry to explain the birth, life, and death of stars, planets, galaxies, nebulae, and other objects in the universe. It is very closely related to astronomy and cosmology.
Astrophysics applies the principles of physics and chemistry to ascertain the nature of astronomical objects, rather than their positions or motions in space. Read more about careers in astronomy and astrophysics.
14. Biophysics
We will post a detailed article on Biophysics very soon.
In the meantime, please feel free to read more about Quantum Computing and Quantum Engineering.
About Parinita Gupta:
Parinita is a full-time banking professional. Additionally, she is also a passionate blogger and digital marketer.
She mostly writes about the Banking & Finance, Technology, and FinTech sector. But, she also enjoys writing on other topics as well. You can follow her on Twitter.
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