We are surrounded by physics all the time. The word 'physics' comes from the Greek 'knowledge of nature'. This field of study aims to analyze and understand the natural phenomena of the universe.
In this lesson, we will understand
Something as simple as walking can be explained by physics. While you walk, you have a good grip and do not slip? This grip is caused by the roughness or resistance between the soles of your feet/shoes and the ground. This roughness or resistance is called "friction". What happens when you accidentally step on a banana peel? You fall! Now, what makes you fall? It happens because the slippery peel reduces friction between your foot/shoes and the surface of the ground.
Do you know if physics had not been there, we wouldn't have been able to write with a ballpoint pen on paper? In this case, the concept of gravity comes into play. As the ballpoint pen moves across the paper, the ball turns and gravity forces the ink down onto the top of the ball where it is transferred onto the paper.
Physics is the study of matter and energy. It is concerned with how matter and energy relate to each other, and how they affect each other over time and through space. This energy can take different forms like light energy, electricity, magnetic energy, gravity, etc. Physics deals with matter ranging from very small particles that make up the atom to particles forming stars and galaxies.
A more elaborate description of physics can be: it is the science that deals with natural objects, laws, and properties of matter, and the forces which act upon them. It is a huge subject with many disciplines.
1. Classical mechanics - It is the mathematical study of the motion of everyday objects and the forces that affect them.
2. Thermodynamics - It studies the effects of changes in temperature, pressure, and volume on physical systems on the macroscopic scale, and the transfer of energy as heat.
3. Electromagnetism and photonics - The study of the behaviors of electrons, electric media, magnets, magnetic fields, and general interactions of light.
4. Relativistic mechanics - It is concerned with the motion of bodies whose relative velocities approach the speed of light or whose kinetic energies are comparable with the product of their masses (m) and the square of the velocity of light (c), or mc2
5. Quantum mechanics - It is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles.
6. Optics and acoustics - Optics is the study of light motions including reflection, refraction, diffraction, and interference. Acoustics is the branch of physics involving the study of mechanical waves in different mediums.
7. Condensed matter physics - The study of the physical properties of matter in a condensed phase.
8. High-energy particle physics and nuclear physics - Particle physics studies the nature of particles and nuclear physics studies the atomic nuclei.
9. Cosmology - It studies how the universe came to be, and its eventual fate. It is studied by physicists and astrophysicists.
Scientists who are experts in physics are called physicists. Some of the most famous scientists in history are considered physicists such as Isaac Newton and Albert Einstein.
Physicists try to understand the fundamental principles that describe and govern all physical aspects of the universe. They investigate by means of controlled experimentation and mathematical analysis. This presents another way to divide physics into two parts - applied or experimental physics and theoretical physics.
Theoretical physicists devise mathematical models to explain the complex interactions between matter and energy. Isaac Newton, Albert Einstein, and Stephen Hawking are famous theoretical physicists. They developed theories about how the universe works.
Experimental physicists use advanced tools like lasers, particle accelerators, and telescopes to conduct tests on specific physical phenomena and arrive at answers. They design and run careful investigations on a broad range of phenomena in nature, often under conditions that aren't usually found in our everyday lives. For example, they may investigate what happens to the electrical properties of materials at temperatures very near absolute zero (-460 0F, -273 0C), or measure the characteristics of energy emitted by very hot gases.
There is a broad overlap between experiment and theory. Experimental physicists remain aware of the current theoretical works in their fields, and theoretical physicists must know the experimenters' results and the context in which the results need to be interpreted.
Physics is a fascinating subject. It attempts to describe how nature works using the language of mathematics. It is considered as the most fundamental of all the natural sciences. It tries to describe the function of everything around us, from the movement of tiny charged particles to the motion of people, cars, and spaceships. In fact, almost everything around you can be described quite accurately by the laws of physics.
The importance of physics to today's society is widely represented by our reliance on technology. Many of the technologies that are continually transforming the world we live in can be directly traced back to important physics research. For example, research on the physics of semiconductors enabled the first transistor to be developed in 1947. The semiconductors form the key component in all of our electronic systems, including computers, enabling advances in communications, computing, healthcare, military systems, transportation, etc. Also, it is the laws of optics describing the way light behaves that have lead to the development of the optical fiber networks that led to internet communication, drawing the world closer together.
