ACCA, MBA, Tax Agent ជាអ្នកនិពន្ធហើយអាចប្រលងជាប់៖ ACCA រហូត ៤ មុខវិជ្ជាក្នុងពេលតែម្តង, Tax Agent ពិន្ទុខ្ពស់, MBA & BBA ជាប់ជាសិស្សពូកែ និងមានបទពិសោធការងារជាង ១៥ ឆ្នាំ ព្រមទាំងអ្នកនិពន្ធផ្សេងៗ ?ទិញឯកសារហើយ អានមិនយល់អាចសួរបាន
mechanics : The branch of science concerned with the behaviour of physical bodies when subjected to forces or displacements and the subsequent effects of the bodies on their environment.
measure of central tendency : A term which relates to the way in which quantitative data tend to cluster around some value. A measure of central tendency is any of a number of ways of specifying this “central value”.
Maxwell’s equations : A set of partial differential equations that, together with the Lorentz force law, form the foundation of classical electrodynamics, classical optics, and electric circuits. Maxwell’s equations describe how electric and magnetic fields are generated and altered by each other and by charges and currents.
matter : Any substance (often a particle) that has rest mass and (usually) also volume.
matrix : A rectangular array of numbers, symbols, or expressions arranged in rows and columns. The individual items in a matrix are called its elements or entries.
mathematics : The abstract study of topics encompassing quantity, structure, space, change, and other properties.
mathematical physics : The application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and for the formulation of physical theories.
mass number:
The total number of protons and neutrons (together known as nucleons) in an atomic nucleus.
mass moment of inertia : A property of a distribution of mass in space that measures its resistance to rotational acceleration about an axis.
materials science : An interdisciplinary field incorporating elements of physics, chemistry, and engineering that is concerned with the design and discovery of new materials, particularly solids.
mass flux : The rate of mass flow per unit area. The common symbols are j, J, φ, or Φ, sometimes with subscript m to indicate mass is the flowing quantity. Its SI units are kg s−1 m−2.
mass density : See density.
mass balance:
An application of the law of conservation of mass to the analysis of physical systems.
magnetism : A property of materials that respond to an applied magnetic field.
magnetic field : A mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude (or strength); as such it is a vector field.
Maclaurin series : A representation of a function as an infinite sum of terms that are calculated from the values of the function’s derivatives at a single point.
machine element : An elementary component of a machine. There are three basic types: structural components, mechanisms, and control components.
machine : Any powered tool consisting of one or more parts that is constructed to achieve a particular goal. Machines are usually powered by mechanical, chemical, thermal or electrical means, and are frequently motorised.
Mach number : A dimensionless quantity representing the ratio of the speed of an object moving through a fluid to the local speed of sound.
M-theory : An extension of string theory that attempts to unify seemingly contradictory mathematical formulations and which identifies 11 dimensions.
liquid crystal (LC): A state of matter which has properties between those of a conventional liquid and those of a solid crystal. For instance, an LC may flow like a liquid, but its molecules may be oriented in a crystal-like way.
liquid : One of four classical states of matter having a definite volume but no fixed shape.
Liouville’s theorem : Phase space volume is conserved.
linear elasticity : The mathematical study of how solid objects deform and become internally stressed due to prescribed loading conditions. Linear elasticity is a simplification of the more general nonlinear theory of elasticity and is a branch of continuum mechanics.
linear algebra : The branch of mathematics concerning vector spaces, often finite or countably infinite dimensional, as well as linear mappings between such spaces.
linear actuator: A form of motor that generates a linear movement directly.
light: A form of electromagnetic radiation that occupies a certain range of wavelengths within the electromagnetic spectrum. In physics, the term sometimes refers collectively to electromagnetic radiation of any wavelength, in which case light includes gamma rays, X-rays, microwaves, and radio waves, but in common usage “light” more often refers specifically to visible light.
lepton : An elementary particle which does not undergo strong interactions but is subject to the Pauli exclusion principle. Two main classes of leptons exist: charged leptons (also known as the electron-like leptons) and neutral leptons (better known as neutrinos).
Laplace–Runge–Lenz vector:
A vector used chiefly to describe the shape and orientation of the orbit of one astronomical body around another, such as a planet revolving around a star. For two bodies interacting by Newtonian gravity, the LRL vector is a constant of motion, meaning that it is the same no matter where it is calculated on the orbit; equivalently, the LRL vector is said to be conserved.
Kirchhoff’s equationsIn fluid dynamics, a set of equations which describe the motion of a rigid body in an ideal fluid.
laminar flow:
Occurs when a fluid flows in parallel layers with no disruption between the layers.
Kirchhoff’s circuit laws:
Two approximate equalities that deal with the current and voltage in electrical circuits. See Kirchhoff’s laws for other meanings of the term.
kinetic energy : The energy that a physical body possesses due to its motion, defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. The body continues to maintain this kinetic energy unless its velocity changes. Contrast potential energy.
kinematics : The branch of classical mechanics that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without consideration of the causes of motion. The study of kinematics is often referred to as the “geometry of motion”.
Kelvin : A scale and unit of measurement of temperature. The Kelvin scale is an absolute thermodynamic temperature scale which uses absolute zero as its null point.
joule : A derived unit of energy, work, or amount of heat in the International System of Units.
isotope : A variant of a particular chemical element. While all isotopes of a given element share the same number of protons, each isotope differs from the others in its number of neutrons.
ionization : The process of converting an atom or molecule into an ion by adding or removing charged particles such as electrons or other ions.
ionic bond : A type of chemical bond formed through an electrostatic attraction between two oppositely charged ions.
ion: An atom or molecule in which the total number of electrons is not equal to the total number of protons, giving the atom a net positive or negative electric charge.
International System of Units (SI) : The modern form of the metric system, comprising a system of units of measurement devised around seven base units and the convenience of the number ten.
inertia : The resistance of any physical object to a change in its state of motion or rest, or the tendency of an object to resist any change in its motion.
impedance : The measure of the opposition that a circuit presents to a current when a voltage is applied.
ice point : A physical process that results in the phase transition of a substance from a liquid to a solid.
homeokinetics : The physics of complex, self-organizing systems.
hertz : The SI unit of frequency, defined as the number of cycles per second of a periodic phenomenon.
heat: A form of energy transferred from one body to another by thermal interaction.
half-life : The time required for a quantity to fall to half its value as measured at the beginning of the time period. In physics, half-life typically refers to a property of radioactive decay, but may refer to any quantity which follows an exponential decay.
gravity : See gravitation.
gravitational wave : A ripple in the curvature of spacetime that propagates as a wave and is generated in certain gravitational interactions, travelling outward from their source.
gravitational potential : The gravitational potential at a location is equal to the work (energy transferred) per unit mass that is done by the force of gravity to move an object to a fixed reference location.
gravitational field : A model used to explain the influence that a massive body extends into the space around itself, producing a force (gravity) on another massive body. Thus, a gravitational field is used to explain and represent gravitational phenomena. It is measured in newtons per kilogram (N/kg).
gravitational energy : The potential energy associated with the gravitational field.
gravitational constant (G):
A physical constant involved in the calculation of gravitational force between two bodies.
gravitation:
A natural phenomenon by which physical bodies attract each other with a force proportional to their masses.
gamma ray : A form of electromagnetic radiation of very high frequency and therefore very high energy.