Physics : definition and applications

Physics is defined as the scientific study which is concerned with describing the interactions of energy, matter, space, and time, and it is especially interested in what fundamental mechanisms underlie every phenomenon.

Applications of physics
Knowledge of physics is useful in everyday situations as well as in nonscientific professions. Physics is the foundation of many important disciplines and contributes directly to others. Some applications of physics are as follows:-

• Engineering :- Most branches of engineering are applied physics. In architecture, physics is at the heart of structural stability, and is involved in the acoustics, heating, lighting, and cooling of buildings.
• Chemistry :- In chemistry knowledge of physics is required to understand the interactions of atoms and molecules.
• Biology :- Physics has many applications in the biological sciences. On the microscopic level, it helps describe the properties of cell walls and cell membranes (Figure 1.6 and Figure 1.7). On the macroscopic level, it can explain the heat, work, and power associated with the human body. Physics is involved in medical diagnostics, such as x-rays, magnetic resonance imaging (MRI), and ultrasonic blood flow measurements. Medical therapy sometimes directly involves physics; for example, cancer radiotherapy uses ionizing radiation. Physics can also explain sensory phenomena, such as how musical instruments make sound, how the eye detects color, and how lasers can transmit information.
• Geology :- Parts of geology rely heavily on physics, such as radioactive dating of rocks, earthquake analysis, and heat transfer in the Earth.

Some disciplines, such as biophysics and geophysics, are hybrids of physics and other disciplines.
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