What is Physics and name of branches of Physics

Q.1: What is Physics? Write the name of branches of Physics and explain them?

Answer: PHYSICS:

Physics is defined as a science which deals with the interaction of matter and energy.


It is the branch of science which deals with physical properties, behavior of matter and bodies. Now a days Physics deals with the production of energy and their mutual relationship.

Main Branches OF Physics:

Main branches of Physics are given below:

  • Mechanics:

It deals with the motion of objects with or without reference of force.

  • Electricity:

It is concerned with the phenomena and effects related to electric charges.

  • Electromagnetism:

It deals with observations, principles, laws and methods that relate electricity and magnetism.

  • Atomic Physics:

It is concerned with the structures and properties of atoms.

  • Solid State Physics:

It is concerned with the structure and properties of solid materials.

  • Nuclear Physics:

Nuclear physics deals with the structures, properties and reactions of the nuclei of Atoms.

  • Astrophysics:

It is concerned with the study of astronomical bodies.


“A branch of physics in which we study the behavior ot heavenly bodies like the moon, stars, the sun and other planets”.

  • Bio-Physics:

It is concerned with the study of biological systems in the light of theories of physics.

  • Plasma Physics:

It is concerned with matter in its plasma phase. Plasma is a state of matter which

Consists of highly ionized atoms, bare nuclei (nuclei without electrons) and electrons.

Q.2: Write down the important role of physics in our daily life?


The importance of Physics in our daily life is given below:

  • Automobile technology is based on the principles of thermodynamics.
  • Nuclear energy is used on a large scale to produce electric power.
  • Radar technology is based on the rules of Physics.
  • Lasers are widely used in medical science.
  • All the electrical devices which are used as home appliances are based on physics rules and laws.

Q.3: What is a scientific method? Write down the names of its steps?


It is a specific method used to search truth and reality.


“The method which helps to collect facts on the basis of observations and experiments is called scientific method”.

Steps Of Scientific Method:

The scientific method includes the following five steps.

  • Observation
  • Hypothesis
  • Theory
  • Experiment
  • Laws

Q.4: Define the steps of a scientific method?


  • Observation:

The process of observing natural phenomenon with the help of five senses and the scientific equipment is called observation. Observations are taken very carefully. All possible information are gathered about a physical phenomenon under investigation

  • Hypothesis:

The explanation of observations and facts is called hypothesis. A hypothesis is a notion or guess of a scientist in which he tries to explain the phenomenon.

  • Theory:

If a hypothesis is accepted, it is called a theory. Scientist designs a theory on the basis of hypothesis and given an elaborated explanation about the phenomenon.

  • Experiment:

Scientists make experiment to test a theory. If theory is proved by experiment, it is regarded correct and accepted. If the theory is not proved by experiments, it is discarded.

  • Laws:
  • When a theory has been thoroughly checked under different situations and it gives the Same results then it becomes a law. The law explains the observations and the experiments about a physical phenomenon.

Q.5: What are the different theories of light?


Newton’s Particle Theory Or Corpuscular Theory:

Newton made a hypothesis about the nature of light. According to Newton’s theory, light consisted of very minute but high velocity particles which were supposed to be originated from a source of light (like the sun). These particles are called corpuscles. According to this theory, the particles of light are travelled very faster in a denser medium than rarer medium.

Huygens’s Wave Theory Of Light:

According to this theory, the particles are travelled through a medium which is called ether. The light particles are travelled faster in rarer medium than the denser medium.

Quantum Theory Of Light:

According to this theory, light has dual nature sometimes it behaves like a wave and sometime like a particle. It consists of packets of energy which are called photon.