Physics is a science that studies the properties of matter and energy, establishing a direct relationship between them. The word “physics” in the dictionary means “the study of matter, energy and the interaction between them”. Furthermore, originating from the Greek term “physiké” which means “nature”, the word “physics” refers to the science that studies nature.

Although the definition given in antiquity is not entirely wrong, a scientific division has resulted in the areas of chemistry and biology. Thus, each of them started to have their own field of studies, including physics.

Physical knowledge, therefore, is mainly based on experiments, observations and mathematical formulations. It is also the role of this knowledge to describe, predict and justify through laws, some situations and phenomena that can occur with a body in space over time.

So, it is the role of physics to study the natural phenomena of matter. However, it is difficult to define an exact field of action for this knowledge. Well, it covers many fields of knowledge, even if you don’t realize it.

What is physics?

Basically, physical knowledge takes place through experimental observations and mathematical laws in order to explain the phenomena of interactions between space, time, matter, motion and energy. Namely that physics is also responsible for describing and explaining the configuration of the fundamental particles of the universe.

The entire universe is composed of particles, so phenomena covered in other sciences can also be explained by physical knowledge. Since, physics describes the dynamics of these particles. Thus, physical knowledge is intertwined with other sciences.

Certainly, physics has as its main objective to explain the workings of the universe. For this, it is based on scientific methodologies and mathematical functions. Undeniably, physical science is the oldest existing field of knowledge. Once it had its beginning marked by astronomical observations made by millenary peoples around the world.

Goals

• Speculative objective :  The speculative objective aims to unravel the enigmas of nature, in order to understand the human relationship with the universe.
• Practical Objective:  In short, the practical objective intends to improve the living conditions of human beings through technology. Thus, it would be possible to perform tasks in a more practical way, improving the quality of life.
• Clarifying Objective: Basically, it analyzes the cause and effect of certain phenomena. However, it is not focused on beliefs and superstitions, showing a difference between them.

Divisions

Physics, like other sciences, is also divided into areas based on several criteria, namely:

• Theoretical: In short, it aims to define new theories through experiences in order to expand knowledge.
• Experimental: It is responsible for the experiments in charge of validating and giving as true, or not, the formulated theories. In the same sense, it can also only correct some defects in the theory.
• Applied: It is basically the application of physical theories in everyday life.

Branches of physics

Undeniably, physics is a very vast science, so it is divided into a few areas to make it easier to understand. The division is made between Classical Physics and Modern Physics.

In short, classical physics encompasses phenomena that are macroscopic, that is, that can be observed. Such as the movement of stars and projectiles, operation of thermal machines, acoustics, geometrical optics, hydrostatics, electrostatics, among others. The knowledge of classical physics was mainly developed by names such as Isaac Newton, Galileo Galilei, Johannes Kepler, Lord Kelvin, among others.

On the other hand, modern physics is responsible for understanding microscopic phenomena, such as those that occur at subatomic scales. In addition to studying bodies that move at speeds close to the speed of light. So, it was from modern physics that phenomena such as radioactive decay, nuclear fissions and fusions, photoelectric effect, etc. were explained.

It is worth remembering that modern physics emerged in the 20th century with the discovery of radioactivity, X-rays, electromagnetic waves and atomic theory.

Classical physics

• Mechanics : In short, mechanical physics comprises the study of particle motion.
• Kinematics: This branch is responsible for analyzing movement without regard to circumstances. In addition, it understands concepts such as position, displacement, velocity, acceleration, etc.
• Dynamics : It is responsible for understanding the forms of energy related to the movements of translation and rotation. In addition, it also studies linear and angular motion and mechanical energy.
• Statics:  In short, it is the area responsible for studying the equilibrium conditions of bodies. Certainly, it is a highly applied branch in civil construction. It deals with concepts such as center of mass, center of gravity, rotational balance and translational balance.
• Electrostatics  and Classical Electrodynamics:  This branch of physics analyzes static and dynamic electrical phenomena. Thus, its object of study is electric charges, electric potential, electric field, Coulomb’s law, magnetism and so on.
• Classical Thermodynamics : In short, it is the field of study of the thermodynamic states of matter, based on thermology and calorimetry. Of course, this division of physical knowledge is complemented by the laws of thermodynamics, which involve the concepts of heat, temperature, entropy, etc.
• Undulating : This is an area of ​​physics that encompasses the propagation of electromagnetic waves and sound waves. Thus, it also addresses the phenomena suffered by waves (reflection, refraction, diffraction, interference, absorption, etc.)

What branches of physics define each?

We can define Physics as the science that studies the most general aspects of nature. … Basically, Physics is divided into 6 branches which are Mechanics, Thermology, Wave Motion, Optics, Electricity and Modern Physics .

What are the branches of modern physics?

The modern physics can be divided into two major branches , quantum mechanics and relativity. In quantum mechanics, the study of very small particles, which did not behave according to classical mechanics, is done.

What does a physicist do?

Most physicists work on research to find answers to fundamental questions. For example, what matter is composed of, how the sun stays lit for so many years, what was the origin of the universe, and so on. These are called pure searches.

While the questions often lead to answers that can lead to a technological advance, they are able to change the way we live our lives. For example, the technologies that we have acquired today were the result of research, experimentation and observations, before being put to use.

Therefore, it is evident that in all sectors of society people with knowledge of physics are needed. For carrying out research, for its application in all spheres of human activity.

The role of physicists in areas such as game development, development of new forms of energy, treatment of diseases and even to develop a conception of natural phenomena is essential.

Main physical formulas

One of the foundations of physics is mathematical formulations, which are used to describe different types of phenomena. As an example, here we will present some essential formulas of physical knowledge.

Newton’s second law

Kinetic energy

Average speed

average acceleration

first law of thermodynamics

fundamental equation calorimetry

sensible heat equation

Electric field

resting energy

Major discoveries from physics to science

Undeniably, there are some milestones in physical knowledge that have helped advance humanity and various technologies. Check the timeline for some of these events:

• 250 BC – Archimedes’ Principle: This physicist developed a theory where an object, when placed inside a fluid, suffers a force of the same weight oriented upwards, causing the object to remain floating.
• 1514 AD – Heliocentrism: Scientist Nicolas Copernicus designed a solar system where the sun is at the center of all other planets in orbit.
• 1687 – Laws of Motion and Universal Gravitation:  Isaac Newton devised three laws of motion and the law of universal gravitation. This happened after the publication of his book: “Mathematical Principles of Natural Philosophy”.
• 1803 – Atomic Theory: The researcher John Dalton developed the theory that the composition of bodies is through a permanent proportion of elements. It was based on the works of Antonie Lavoisier and Joseph Proust.
• 1831 – Electromagnetic Induction: Michael faraday studied the magnetic field, and noted that the variation of this flux promotes induced electrical currents in conductive materials.
• 1838 – Earth’s magnetic field : It was physicists Wilhelm Weber and Carl Gauss who developed the theory that planet earth produced a magnetic field.
• 1864 – Maxwell’s Equations:  This equation, developed by physicist James Clerk Maxwell, was nothing more than the unification of the equations of electricity with the equations of electromagnetism.  In addition, he also calculated the speed of light.
• 1896 – Radioactivity :  Physicist Henri Becquerel discovered  radiation  through radioactive elements.
• 1897 – Discovery of the electron :  JJ Thomson discovered the electron, which was a particle opposite the proton  and with a smaller mass.

Physical quantities

The physical quantities is nothing more than the amount of variations of the rating, that is, units of measure. Undeniably, these units of measure vary depending on location. The physical quantities are divided into two, as follows:

Scalar quantities: Knowing that they are those that have real numbers, negative or positive, and are always accompanied by their unit of measure.

Vector quantities: In short, they are characterized by having module, direction and meaning.