Scope of Physics

Introduction to physics

Physics is the branch of science concerned with the nature and properties of matter and energy. The subject is diverged into mechanics, heat, light and radiation, sound, electricity, magnetism, and the structure of atoms. Physics is the oldest subject because, from the time immemorial, people have realized that there is some natural force driving every act that takes place in our surrounding is due to some natural force.However, they were not clear about whether these were scientific, measurable and can be classified under physics. They believed that,  some of the natural phenomenon such as raining, thunders, storms, the formation of clouds, are all driven by the basic principles of gravitation, force, speed, velocity and many more. But these were lacking a  proper scientific approach with a clear explanation due to minimum empirical evidences . Later on, as the scientific era has grown into new heights, the physics as a discipline has expanded into many super-specializations such as the astronomy, nuclear physics, thermodynamics, optics, atomic physics, etc. Some of the significant topics of the academic physics are mechanics, heat, thermodynamics, electromagnetic concepts,  optics, energy, force, units of measurement, atomic and nuclear physics, astrophysics, etc. Every specialization serves some particular areas of interest and the same is applicable in physics.  Some of the essential areas of interest in physics are discussed below.


Areas of physics

Some of the most useful areas of physics are mechanics, heat and thermodynamics, electromagnetism etc. Mechanics is a discipline deals with the motion of particles and general systems of particles. Heat and thermodynamics deals with how heat can change the dynamics or how heat and cold are related with volume, pressure, gravity of an object, for example; when the rice is being pressure cooked, the heat energy is converted into pressure resulting in popping up of cooker`s weight. Electromagnetism is a discipline that deals with 2 fields, namely electric field, and magnetic field and how they behave when they act together. Optics help us to understand the surfaces of mirrors, glasses and its nature, and set of behaviours of these objects under different external conditions. Atomic and nuclear physics deals with the atoms, their structure, properties, distribution, and behaviours.It is most widely used in different industries. The major areas of atomic physics deals with the protons, neutrons and electrons. Atomic physics elaborate one`s knowledge about  atomic weight, atomic force, atomic energy, and atomic composition. Nuclear physics is closely related with atomic physics that help us to explain the nuclear energy production, usage of nuclear energy for the benefit of mankind as well as and their ill effects. 


Physics as a discipline

Physics is a branch of natural science, the word physics is derived from ἡφύσις , Greek word meaning ‘nature’. Physics describes various natural phenomena with the help of theories and laws. The 2 major principles of physics are the Unification and reduction. Unification is when we use a single theory to explain 2 or more phenomena in nature. For example, electricity and magnetism are two different phenomena, but it all comes under the theory of electromagnetism in physics. On the other hand, reduction  is the effort to solve a complex problem by breaking it into simpler parts, for example, Temperature of a system is reduced to average kinetic. The scope of physics can be better understood by looking at the sub-disciplines of physics as shown below in the flow chart. The subtopics of physics can be put into the macroscopic domain and the microscopic domain as shown below.


Factors responsible for the progress of physics

Some of the major channels through which physics has boomed into a broad discipline are the hypotheses, axioms, and modals. The 3 laws  help us to understand the cause-effect relationships of many scientific phenomena of our day-to-day observations. 


Hypothesis, axioms, and modals

Every phenomenon that happens around us cannot be proved, but we can only verify or substantiate. A hypothesis is a supposition without assuming that it is true. It would be unfair to ask someone to prove the universal law of gravitation, because it cannot be proved. It can be verified and substantiated by experiments and observations. Hypothesis is an idea that can be verified by experiments and observations. Axiom is a well-established true statement which can be supported by the ample evidences. Modal is a proposed theory to explain particular phenomena.


Concept of classical physics and modern physics

Classical physics deals with what we see in the day-to-day life but modern physics necessitates advanced-level maths with an ability to conceptualize the invisible things. Modern physics includes those concepts and principles that have emerged after the beginning of the 20th century.  Some of the topics dealt under modern physics are the theory of relativity, quantum physics, astrophysics,  nuclear physics, particle physics, and quantum field theory.


Additional questions

  1. Define physics.

  2. Mention any 4 disciplines where the knowledge of physics is applicable.

  3. Differentiate between classical physics and modern physics.

  4. What is thermodynamics?

  5. Differentiate between hypotheses, axioms, and modals.






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