Home » Science » Physics

## Physics

What is physics? The study of physics involves the motion of matter through time and space. Emphasis within physics is centered on energy and force and defining the laws of nature which govern how our universe behaves. It is classified in the realm of physical science as a physicist examines the natural laws that define the world around us. Philosophical thoughts are one factor which drive scientific minds to pursue the knowledge of the physical world. An idea provides the spark which begins the cycle of scientific analysis and exploration into answering a question. Many times the path to finding an answer raises a myriad of questions when the physical laws of nature are put to the test.

### Branches of Physics

Physics is a fairly broad branch of science which finds its self intertwined with the other branches of physical science. Physics utilizes mathematic equations to define the natural world and investigates the energy and forces that drive our universe. Gravity, time and space are all concepts which are vastly unexplored and of great interest to scientists around the globe. Academic disciplines allow physicists to specialize in a particular area of study when pursuing a scientific career.

### Laws of Physics

The laws of physics are a system of explanations for the fundamental forces which govern our world. Although many may think these laws are set in stone, in reality the universe is much more complex than could be imagined. Because of this many of these laws tend to hold true under most circumstances, but there are always variations being discovered under unique situations which make physicists and scientists question the validity of what we believe to be defined.

#### Newton’s Laws of Motion

Newton’s laws of motion state that an object in motion will remain in motion until influenced by another force. This is actually an accumulation of three laws combined to make the generalized statement above. The first law states that an object’s velocity will remain the same if it experiences no influence from forces. Meaning that an object with a net velocity of 0 (not moving) will remain in that state while an object with any velocity value (moving) will remain to move in a straight line until further influence applies. The second law states that the acceleration of an object is is parallel to the direction of force and is inversely counted by the mass of the object (F = ma). The third law states that an object which exerts force on a secondary object will in return receive simultaneous force exerted back on it in an opposing direction. This law describes the concepts of friction and how this degenerates the force applied to create movement in an object.

#### Newton’s Law of Gravity

Newton’s laws of gravity state that within the universe every object with mass will attract other objects with mass which is proportionate to the product of mass and the square of the distance that separates the objects. This was founded by Newton during a series of empirical observations which make up what is now considered to be a general physical law. Like most scientific discoveries, this was not the sole work of Newton, however a collection of scientific minds were hard at work looking into these theories. Newton was simply the first person to describe and publish his findings on the subject crediting it to his success. Another scientist, Robert Hooke was hard at work on the principles of gravity and controversy spurred between the two minds.

#### Laws of Thermodynamics

The laws of thermodynamics are made up of 4 laws which explain the behaviors of energy, temperature and entropy as well as proclaiming impossibilities such as perpetual motion. A system is described to be in thermodynamic equilibrium when it is in thermal, chemical, mechanical and radiative balance. This means that removing the system from its surroundings will not change the state of the system.

#### Quantum Physics

Quantum physics is a sub science which deals with atomic and subatomic particles as well as defining the laws of physics on a microscopic scale. Quantum mechanics explains the interaction of energy and matter on an atomic and subatomic scale and ties into thermodynamics along with other disciplines of physics. One of the primary areas of concern in quantum mechanics deals with how photons interact with the world around us. Since photon particles have next to no mass they are considered to be the objects which can gain the most speed, thus light speed is currently considered to be the fastest an object can travel.

#### Particle Physics

This sub-discipline involves the investigation of the interactions and existence of particles and how they behave based on thermodynamic properties. Particle physics typically studies matter, radiation, and decay and is instrumental in the development of nuclear technology. Today the focus of the discipline is on subatomic particles including electrons, protons and neutrons. The ideology of subatomic particles began with Greek philosophers who theorized that all matter was made up of smaller building blocks or elementary particles. This would be later elaborated on by physicists and scientists alike with the discovery of technologies such as the microscope.

#### Theory of Relativity

The theory of relativity was credited to Albert Einstein and is made up of two theories combined including general relativity and special relativity. This theory introduced the concepts of measurements relative to the observer, space, time and the speed of light. Originally the relative theory was presented by a German scientists Max Planck in the year of 1906 which was later elaborated on by Einstein during his scientific research. Alfred Bucherer was another German scientist who was the first to coin the term “theory of relativity” in the same paper published by Max Planck.

### Scientific Method

When an observation is made by a scientist in which they want to test the cause of the observation, the scientific method is generally applied to conduct these tests. The scientific method is a system of acquiring knowledge and data through techniques which analyze, test and record data in order to prove or disprove a hypothesis. The scientific method relies on unbiased observations with controlled variables to ensure that true knowledge is acquired which has not been skewed from a biased source.

#### Hypothesis

A hypothesis is commonly described to grade school children as an educated guess. In the scientific community it is sometimes described as a proposed outcome, phenomenon or explanation. A hypothesis is a statement which pertains to the causality of an event or phenomenon in which a scientist attempts to reproduce the event and outcome.

#### Model

A model is used to illustrate or demonstrate a situation which is not true in all aspects, but the fundamental principles hold true in most cases. This is commonly used to explain an event, behavior or phenomenon which results from a complex interaction in a manner which is easier to understand. The Bohr model of the atom is an excellent example of this concept, where the electrons are illustrated as revolving like planets in our solar system when in actuality there is no distinct orbit of an electron around a nucleus.

#### Theory

A scientific theory is an idea which has been based on a series of collections of data, hypotheses and observations which has been repeatedly tested over the course of several years. A theory is an idea or hypothesis which still has the potential of being proven wrong and may not apply to all circumstances of an event.

#### Law

A scientific law is devised off the repeated testing of a theory. A set of laws will often define a variety of events in which an outcome can occur differently. Laws are considered to be proven scientific phenomenon which result from years of retesting a theory. Typically a law will also have a scientific equation associated with it as well.