What is Physics?
The definition of physics is the study of the physical plane of matter, motion, force, and energy. The root word of physics is Phys- and is Greek for "nature" and "natural order." Physics itself is studying the natural world and the interactions between objects and energy in any given environment.
In ancient Greece, early scientists did not have anything more than their senses to help them study the world around them. These scientists often studied their environment through touch, taste, smell, sight, and sound. During the 17th century, people like Galileo, Copernicus, and Newton revolutionized science with breakthroughs of physics through the laws of gravity, the sun-centered theory, and the discovery of atoms. With modern technology and advances in the scientific method, physics incorporates things that are not observable to the naked eye.
Is Physics Science?
Is physics science? This question may seem obvious, but is physics considered science or art? Science is defined as a compilation of observations, predictions, and organizational methods of testing the universe. Art is an individual's expression of their experiences through creative skill.
The answer is yes; physics is a science. Since physics concerns itself with observations and testable predictions about the physical universe and not someone's opinion of said universe, it is most definitely a science.
Branches of Physics
The physical universe has many moving parts and is not simply what is observed through the naked eye. Physics is also how the most prominent objects interact with the smallest and everything in between. Since physics is such a broad subject, it has to be broken into smaller categories or disciplines, also known as fields of study.
There are three main categories of modern physical study:
- Classical physics covers electromagnetism, classical mechanics, thermodynamics, and statistical mechanics. Classic physics provides action and reaction, showing how objects acting in a system will interact with other objects in that same system.
- Relativity has two types of study; there is general and specific relativity. General relativity deals with how the law of gravity interacts with objects; this has a significant bearing in astrophysics and astronomy. Special relativity concerns how objects interact in a vacuum or are devoid of gravity.
- Quantum physics is the most recent course of study in physics. Here, scientists study quantum mechanics, quantum statistics, quantum electrodynamics, and quantum field theory. This branch deals primarily with objects at an atomic and subatomic level. It answers questions like, "what makes a proton different from a neutron?"
The study of mechanics is both broad and specific. Broadly, mechanics study objects, their motion, energy, and how they interact with other objects and energy. There are two sub-branches of mechanics, quantum mechanics and classical mechanics.
- Quantum mechanics, studies how atom and subatomic particles act and react with one another; similar to how the atom is held together, what happens if two atoms collide? What makes up the atomic particles; how and why do two atoms bond; what holds together millions of atoms into a complex compound?
- Classical mechanics follows the same principles as quantum, at a much larger scale. Examples of classical mechanics would be predicting planetary orbits or the path of a bullet, black holes, friction between a car tire and the road, why water has surface tension, or the arc of a baseball as it is thrown across home plate.
Mechanics can explain a minor interaction, like why an electron is attracted to a proton, and the most significant interaction, like why the earth orbits the sun.
One of our two most important senses is that of sight. In physics, the study of light and its properties is called optics.
One reason light is a fascinating study subject is that it contains the properties of a wave and particles. Additionally, electromagnetic waves make up light, meaning it has properties of electricity and magnetism and does not need a medium to move.
There are several different types of light:
- Radio Waves
- Gamma Rays
Similar to mechanics, thermodynamics covers a broad range of studies. Thermo-heat and dynamics-relationships is the study of relationships between heat and other forms of energy.
For example, due to oceans covering a significant part of Earth, Earth does not experience large swings in overall temperature because water holds in heat better than dirt and keeps life going on this planet. Fewer oceans would result in temperatures between night and day, summer and winter being too large to sustain many life forms. The relationship between heat held in water versus heat given up by water is vital to study and understand.
There are three laws of thermodynamics, which govern the interaction between heat and energy in a system:
- First Law: Energy can change its form, but not amount.
- Second Law: Entropy of any system ascends towards chaos or the loss of useable energy.
- Third Law: Entropy is at its smallest when the temperature of a system approaches absolute zero.
Electromagnetism is the manipulation of electric currents and fields along with magnetic fields. Electricity and magnetism require a medium or an object to work through. Elements like gold and copper are good conductors. These conductors allow the flow of electricity due to their atomic layout. Not only are there good conductors, but there are also good insulators. Silicon is a good insulator; it does not allow the passage of energy easily.
Michael Faraday, an English scientist from the 19th century, hypothesized that electricity and magnetism ran in lines of force. He observed iron filings lining up end to end on a magnet, which supported his theory. Faraday also created a magnet using electricity.
The branch of physics that studies the properties of sound is called acoustics. Sound is created by mechanical vibrations or movement within all forms of matter. However, while acoustics is a part of physics, it permeates many different aspects of study, whether science or art.
For example, biologists study hearing, as it is one of the most important senses, and geologists study earthquakes due to their substantial seismic and acoustic waves. Additionally, sound dampening is an important property to consider in engineering, and music is an art that is hugely dependent on sound and vibrations.
Albert Einstein is probably the most famous of modern scientists. One of Einstein's most important contributions to science is the theory of relativity, both general and special. He theorized that forces, like gravity, can be experienced differently by objects moving at different speeds. Gravity itself is a distortion of space and time. Time does not move in a straight line as previously believed; someone who is moving at the speed of light will age differently than someone moving much more slowly. The phenomenon is only relative to the observer.
Importance of Physics
Physics is the oldest science and can be concluded as the most important. As observers and participants in life, humans need to understand and explain their world, which will allow for the understanding of the environment, leading to the manipulation of that environment. Due to physics, things like electricity, magnetism, temperature, relativity, the atom have been studied and put into practical use; household items such as water heaters, lights, and plumbing can all be attributed to a discovery in the realm of physics.
Since physics is essentially the study of the whole environment, it has led to advances in other areas of science as well. For example, chemistry and thermodynamics study go hand in hand; acoustics is essential in biology and sociology to understand how humans interact; art and music depend on the artist or musician's innate understanding of light and sound.
Physics is the scientific study of nature, focusing on the physical plane of motion, force, and energy and comes from the root Phys, Greek for "nature" and "natural order."
There are several branches of physics:
- Mechanics: The study of bodies in motion
- Optics: The study of light and its properties
- Thermodynamics: The energy of a system and how it changes
- Electromagnetism: A combination of opposite charges and the energy fields they create
- Acoustical: The study of sound and the apparatuses and vibrations it causes
- Relativity: General relativity is with gravity, and specific relativity is without gravity; space and time are different for different observers
Physics is the oldest and most important aspect of science. It bleeds into multiple areas, like music, art, and biology, ultimately setting the framework for other areas of study.
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What are the 7 branches of physics?
The seven branches of physics are optics, electromagnetism, relativity, thermodynamics, acoustics, quantum physics, and mechanics. There are smaller categories within these broad areas.
What is physics in simple terms?
Physics is the study of the natural world, both seen and unseen. It is a broad subject that can be broken down into specific areas of study, like electromagnetism and optics.
What is physics and why is it important?
Physics is an important area of study because it allows scientists to understand the world, the environment, and the interactions between objects in a system. Understanding our world allows for appreciation, conservation, innovation of the world around us.
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