Most sciences are divided into branches or disciplines, according to the specialisation that takes place within each of them. It is also the case of physics, the science in charge of studying matter and energy. In this article we will learn about the 12 most important branches of physics.
We will know what physics consists of, what are its two divisions (classical and modern physics) and the 12 most important branches of this science.
Physics: What is this science?
Physics is the science that has as its object the study of matter and energyIt studies the properties of these, their phenomena, processes, composition, structure, etc. In addition, it establishes laws that make it possible to explain and understand certain natural phenomena.
This is a very broad science, which is diversified into different branches. Each of them has a different object of study and specific characteristics.
The 12 Branches of Physics
Before explaining the different branches of physics, we must specify that physics is divided into two very broad branches: classical physics and modern physics. Classical physics studies those phenomena with a lower speed than the speed of light; on the other hand, it uses scales superior to those of molecules and atoms.
By contrast, modern physics (the one used after the appearance of relativistic theories) studies the following phenomena occurring at the speed of lightThe scales it uses are mainly atomic scales. This second branch is newer, and its beginnings date back to the beginning of the 20th century.
The 12 branches of physics that we are going to explain correspond to branches of both classical and modern physics:
The first of the branches of physics that we are going to explain is nuclear physics. This branch is, in turn, a field of physics, which is responsible for studying atomic nuclei. It also studies the interactions that occur between atomsparticles and other substances or physical elements relevant to the atomic level.
The physicists and/or scientists who laid the foundations of mechanics were: Galileo, Newton, Kepler and Jayam.
Mechanics, another of the branches of physics, is dedicated to describing the nature of physical bodiesand studies their behaviour when they are subjected to forces or displacements. It also studies the effects of these bodies with the environment, as well as the movement of forces on different objects and particles. But what are physical bodies? This category includes virtually anything with mass, such as particles, stars, machine parts, parts of solids and fluids (liquids and gases), projectiles, spacecraft, etc.
Quantum mechanics is a branch of modern physicsIt is responsible for studying the behaviour of light and matter at the atomic and subatomic scales. It aims to describe the properties of molecules and atoms; it analyses their components (electrons, protons, neutrons…) and their structure. It also focuses on the study of more complex and tiny particles, such as quarks.
On the other hand, it analyses the interactions between the different particles and describes the properties of light, X-rays and gamma rays (a type of electromagnetic radiation).
4. Fluid Mechanics
This branch of physics studies the flow of liquids and gases. Other sub-disciplines of physics, such as aerodynamics and hydrodynamics, appear from this branch. The first studies air and moving gases, and the second studies moving liquids.
Fluid mechanics, also called fluid dynamics, makes it possible to calculate aircraft forces, determine the mass of fluids such as oil, predict weather patterns, etc.
Thermodynamics, the next branch of physics, studies the effects of energyheat and work in one or more systems. That is, to study the interactions between heat and other sources or manifestations of energy. The origin of thermodynamics goes back to the 19th century, when the value machine appeared.
In addition, this branch has the function of describing the states of thermodynamic equilibrium at the macroscopic level (on a large scale).
Acoustics is the branch of physics in charge of studying sound. Sound involves the movement of mechanical waves; acoustics studies these waves in liquid substances, gases and solids. It focuses on how sound is produced, transmitted, controlled and received. It also studies the effects it produces.
Biophysics, besides being a branch of physics, is also a branch of biology, because is at the crossroads of these two sciences.. It is in charge of studying biology through physical principles, applying physical methodology to biological systems.
Optics studies vision and light; it deals with their properties, processes and phenomena. In addition, it studies and describes the behaviour of light (visible, infrared and ultraviolet light); that is, it studies, for example, how it interacts with matter. Another of its functions is to build instruments related to light and vision, like lenses.
The purpose of electromagnetism is to study electrical and magnetic phenomena. It groups these two types of phenomena into a single discipline. It describes the interactions between electrically and magnetically charged particles (through force and energy fields).
Astrophysics too is considered a branch of astronomythe science that studies the stars (their structure, composition, location…). For its part, astrophysics studies the physics of the stars, focusing on their properties, phenomena, processes, evolution, structure…
Cosmology is considered one of the branches of modern physicsalong with quantum mechanics, nuclear physics and others. This branch studies the Universe on a large scale; it studies its structures and dynamics, its origin, evolution and final destiny.
This branch of physics, considered a science, has its origins in the time of Copernicus and Newton. Copernicus established the principle that heavenly bodies obey the same physical laws as the bodies of the earth. The beginnings of physical cosmology, on the other hand, date back to the beginning of the 20th century, with Einstein’s theory of relativity.
Geophysics is the branch of physics (and also of geology). who studies earth physicsi.e. the physical fields linked to planet earth. We can distinguish two subdisciplines within geophysics: internal geophysics (which studies the interior of the Earth) and external geophysics (which studies the physical properties of the earth’s environment).
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