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What does physics study?
Which branch of physics studies macroscopic objects through time and space?
Which branch of physics studies larger material bodies?
How does physics explain the nature of different objects?
The branch of physics that is the general study of the microworld of photons, atoms, and nuclei. solid state physics. the study of all properties of solid materials, including electrical conduction in crystals of semiconductors and metals, superconductivity and photoconductivity. condensed matter.
- Overview
- The scope of physics
- Mechanics
Physics is the branch of science that deals with the structure of matter and how the fundamental constituents of the universe interact. It studies objects ranging from the very small using quantum mechanics to the entire universe using general relativity.
Why does physics work in SI units?
Physicists and other scientists use the International System of Units (SI) in their work because they wish to use a system that is agreed upon by scientists worldwide. Since 2019 the SI units have been defined in terms of fundamental physical constants, which means that scientists anywhere using SI can agree upon the units they use to measure physical phenomena.
physics, science that deals with the structure of matter and the interactions between the fundamental constituents of the observable universe. In the broadest sense, physics (from the Greek physikos) is concerned with all aspects of nature on both the macroscopic and submicroscopic levels. Its scope of study encompasses not only the behaviour of objects under the action of given forces but also the nature and origin of gravitational, electromagnetic, and nuclear force fields. Its ultimate objective is the formulation of a few comprehensive principles that bring together and explain all such disparate phenomena.
(Read Einstein’s 1926 Britannica essay on space-time.)
Physics is the basic physical science. Until rather recent times physics and natural philosophy were used interchangeably for the science whose aim is the discovery and formulation of the fundamental laws of nature. As the modern sciences developed and became increasingly specialized, physics came to denote that part of physical science not included in astronomy, chemistry, geology, and engineering. Physics plays an important role in all the natural sciences, however, and all such fields have branches in which physical laws and measurements receive special emphasis, bearing such names as astrophysics, geophysics, biophysics, and even psychophysics. Physics can, at base, be defined as the science of matter, motion, and energy. Its laws are typically expressed with economy and precision in the language of mathematics.
The traditionally organized branches or fields of classical and modern physics are delineated below.
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Mechanics is generally taken to mean the study of the motion of objects (or their lack of motion) under the action of given forces. Classical mechanics is sometimes considered a branch of applied mathematics. It consists of kinematics, the description of motion, and dynamics, the study of the action of forces in producing either motion or static equilibrium (the latter constituting the science of statics). The 20th-century subjects of quantum mechanics, crucial to treating the structure of matter, subatomic particles, superfluidity, superconductivity, neutron stars, and other major phenomena, and relativistic mechanics, important when speeds approach that of light, are forms of mechanics that will be discussed later in this section.
In classical mechanics the laws are initially formulated for point particles in which the dimensions, shapes, and other intrinsic properties of bodies are ignored. Thus in the first approximation even objects as large as Earth and the Sun are treated as pointlike—e.g., in calculating planetary orbital motion. In rigid-body dynamics, the extension of bodies and their mass distributions are considered as well, but they are imagined to be incapable of deformation. The mechanics of deformable solids is elasticity; hydrostatics and hydrodynamics treat, respectively, fluids at rest and in motion.
The three laws of motion set forth by Isaac Newton form the foundation of classical mechanics, together with the recognition that forces are directed quantities (vectors) and combine accordingly. The first law, also called the law of inertia, states that, unless acted upon by an external force, an object at rest remains at rest, or if in motion, it continues to move in a straight line with constant speed. Uniform motion therefore does not require a cause. Accordingly, mechanics concentrates not on motion as such but on the change in the state of motion of an object that results from the net force acting upon it. Newton’s second law equates the net force on an object to the rate of change of its momentum, the latter being the product of the mass of a body and its velocity. Newton’s third law, that of action and reaction, states that when two particles interact, the forces each exerts on the other are equal in magnitude and opposite in direction. Taken together, these mechanical laws in principle permit the determination of the future motions of a set of particles, providing their state of motion is known at some instant, as well as the forces that act between them and upon them from the outside. From this deterministic character of the laws of classical mechanics, profound (and probably incorrect) philosophical conclusions have been drawn in the past and even applied to human history.
Lying at the most basic level of physics, the laws of mechanics are characterized by certain symmetry properties, as exemplified in the aforementioned symmetry between action and reaction forces. Other symmetries, such as the invariance (i.e., unchanging form) of the laws under reflections and rotations carried out in space, reversal of time, or transformation to a different part of space or to a different epoch of time, are present both in classical mechanics and in relativistic mechanics, and with certain restrictions, also in quantum mechanics. The symmetry properties of the theory can be shown to have as mathematical consequences basic principles known as conservation laws, which assert the constancy in time of the values of certain physical quantities under prescribed conditions. The conserved quantities are the most important ones in physics; included among them are mass and energy (in relativity theory, mass and energy are equivalent and are conserved together), momentum, angular momentum, and electric charge.
- Classical Mechanics. This branch of physics studies the motion of macroscopic objects through time and space. Newton’s Laws of Motion form the foundation of classical mechanics.
- Thermodynamics. Thermodynamics is the study of heat and temperature. It also correlates heat with energy and work. Heat, temperature, energy etc. are governed by the Four laws of Thermodynamics.
- Quantum Mechanics. Quantum mechanics entails the study of energy levels in atomic and subatomic particles. Quantum field theory is one of the most important principles of quantum mechanics as it connects it with relativity and classical mechanics.
- Electromagnetism. The physical reaction between particles carrying electrical charges can be defined as electromagnetic force. The study of electromagnetic force forms the crux of electromagnetism.
There are many branches of classical mechanics, such as: statics, dynamics, kinematics, continuum mechanics (which includes fluid mechanics), statistical mechanics, etc. Mechanics: A branch of physics in which we study the object and properties of an object in form of a motion under the action of the force.
A branch of classical physics that deals with the study of the physical properties of light and it's nature and behavior. Atomic physics. A branch of modern physics that studies the properties of matter at the atomic scale and examines the structure, behavior and properties of atoms. Biophysics.
Section Learning Objectives. By the end of this section, you will be able to do the following: Describe the definition, aims, and branches of physics. Describe and distinguish classical physics from modern physics and describe the importance of relativity, quantum mechanics, and relativistic quantum mechanics in modern physics.
6 days ago · The physics is used to explain all the reasons why the world works this way and not otherwise, is one of pure science that studies the properties of time, space, matter and energy, as well as the interaction between themselves and other forces.