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What is Physics?
 

Physics is the branch of science concerned with the nature and properties of matter and energy.
 

The subject matter of physics includes mechanics, heat, light and other radiation, sound, electricity, magnetism, and the structure of atoms.
 

Physics is the natural science that involves the study of matter and its motion through space and time, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.
  

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What is Classical Physics?
 

Classical physics includes the traditional branches and topics that were recognized and well-developed before the beginning of the 20th century. i.e. classical mechanics, acoustics, optics, thermodynamics, and electromagnetism.

 

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What is Modern Physics?
 

Modern physics is concerned with the behavior of matter and energy under extreme conditions, or on a very large or very small scale. For example, atomic and nuclear physics studies matter on the smallest scale at which chemical elements can be identified.
  

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What is Classical Mechanics?
 

Classical mechanics is concerned with bodies acted on by forces and bodies in motion and may be divided into statics (study of the forces on a body or bodies not subject to an acceleration), kinematics (study of motion without regard to its causes), and dynamics (study of motion and the forces that affect it).
 

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What is Fluid Mechanics?
 

Fluid mechanics is the branch of physics which involves the study of fluids (liquids, gases, and plasmas) and the forces on them. Fluid mechanics can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.
 

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What is Solid Mechanics?

 

Solid mechanics is the branch of continuum mechanics that studies the behavior of solid materials, especially their motion and deformation under the action of forces, temperature changes, phase changes, and other external or internal agents.

Solid mechanics is fundamental for civil, aerospace, nuclear, and mechanical engineering, for geology, and for many branches of physics such as materials science.

 

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What is called a ‘state of matter’?
 

A state of matter is one of the distinct forms that matter takes on.
 

Four states of matter are observable in everyday life: solid, liquid, gas, and plasma.
 

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What is a ‘plasma’?
 

Plasma is one of the four fundamental states of matter, the others being solid, liquid, and gas.
 

A plasma has properties unlike those of the other states.
 

A plasma can be created by heating a gas or subjecting it to a strong electromagnetic field applied with a laser or microwave generator. This decreases or increases the number of electrons, creating positive or negative charged particles called ions, and is accompanied by the dissociation of molecular bonds, if present.
 

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What is a ‘particle’?
 

A particle is a minute fragment or quantity of matter.
 

In the physical sciences, the word is used to describe a small localized object to which can be ascribed several physical or chemical properties such as volume or mass; subatomic particles such as protons or neutrons; and other elementary particles. 

 

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What is Temperature?

It is the property that determines the degree of hotness or coldness or the level of heat intensity of a fluid.

Temperature is measured by using temperature scales.

There are 3 commonly used temperature scales. They are:

1. Celsius (or centigrade) scale

2. Fahrenheit scale

3. Kelvin scale (or absolute temperature scale)

Kelvin scale is widely used in engineering. This is because, this scale is independent of properties of a substance.