Key Difference: Physics is the study of matter, as well as its motion through space and time, and how it reacts with heat, light, electricity, and sound. Physics also strives to study and understand the related forces such as energy and force. Applied physics deals with practical physics, i.e. the study of things for practical application. Applied physics is a segment of physics that is intended for a particular technological or practical use.

 Physics is one of the subjects of natural science. Natural science is a branch of science that deals with understanding of natural phenomena, i.e. phenomenon that occurs in the universe. Natural sciences use observational and empirical evidence to study a phenomenon and attempt to understand it.

Natural science can de distributed into 2 main branches: life science and physical science. Life science is the study of understanding life, basically it is biology. Whereas, physical science is the study of the physical world; it includes the fields of physics, astronomy, chemistry, and Earth science.

Physics is the study of matter, as well as its motion through space and time, and how it reacts with heat, light, electricity, and sound. Physics also strives to study and understand the related forces such as energy and force. Physics is basically the study of the universe, what make the universe and how the universe operates. It aims to understand natural phenomenon using observational and empirical evidence.

 Physics can be divided into various segments of which one is applied physics. Applied physics deals with practical physics, i.e. the study of things for practical application. Applied physics is a segment of physics that is intended for a particular technological or practical use.

Applied physics may not be directly involved with developing new technology, however, it studies physics concepts with the aim of understanding them and applying them in such a way as to be able to build or help in building new technology.  Applied physics is closely related with engineering, as they both are concerned with applying physics that is understood and useful to new technologies.

Hence, the main difference between Physics and Applied Physics is that Physics is field of study of the natural phenomenon, whereas applied physics is a field of study under physics.

Comparison between Physics and Applied Physics:

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