Mechanical equilibriumIn classical mechanics, a particle is in mechanical equilibrium if the net force on that particle is zero. By extension, a physical system made up of many parts is in mechanical equilibrium if the net force on each of its individual parts is zero. In addition to defining mechanical equilibrium in terms of force, there are many alternative definitions for mechanical equilibrium which are all mathematically equivalent.
Periodic functionA periodic function is a function that repeats its values at regular intervals. For example, the trigonometric functions, which are used to describe waves and other repeating phenomena, are periodic. Many aspects of the natural world have periodic behavior, such as the phases of the Moon, the swinging of a pendulum, and the beating of a heart. The length of the interval over which a periodic function repeats is called its period.
Alternating currentAlternating current (AC) is an electric current that periodically reverses direction and changes its magnitude continuously with time, in contrast to direct current (DC), which flows only in one direction. Alternating current is the form in which electric power is delivered to businesses and residences, and it is the form of electrical energy that consumers typically use when they plug kitchen appliances, televisions, fans and electric lamps into a wall socket.
PendulumMechanism for regulating the speed of clocks"Simple gravity pendulum" model assumes no friction or air resistance.A pendulum is a mechanical device consisting of a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting mechanical equilibrium position, it is subject to a restoring force due to gravity, which will accelerate it back toward the equilibrium position.
Business cycleIntervals of expansion and recession in economic activityBusiness cycles are intervals of general expansion followed by recession in economic performance. The changes in economic activity that characterize business cycles have important implications for the welfare of the general population, government institutions, and private sector firms. There are many definitions of a business cycle. The simplest defines recessions as two consecutive quarters of negative GDP growth.
GeyserA geyser (, UK: ) is a spring with an intermittent water discharge ejected turbulently and accompanied by steam. The formation of geysers is fairly rare and is caused by particular hydrogeological conditions that exist only in a few places on Earth. Generally, geyser field sites are located near active volcanic areas, and the geyser effect is due to the proximity of magma.
EcologyEcology (from Ancient Greek οἶκος (oîkos) 'house' and -λογία (-logía) 'study of') is the natural science which studies the interactions between organisms and their environments. Ecology considers organisms at the community, ecosystem, and biosphere levels. Ecology overlaps with the sciences of biogeography, evolutionary biology, genetics, and ethology.
Dynamical systemIn mathematics, a dynamical system is a system in which a function describes the time dependence of a point in an ambient space, such as in a parametric curve. Examples include the mathematical models that describe the swinging of a clock pendulum, the flow of water in a pipe, the random motion of particles in the air, and the number of fish each springtime in a lake.
EconomicsSocial science studying goods and servicesEuro coinsEconomics () is a social science that studies the production, distribution, and consumption of goods and services. Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analyses what is viewed as the basic elements of economies, including individual agents and markets, their interactions, and the outcomes of those interactions.
GeologyScientific study of Earth's physical compositionNot to be confused with Geography.The Grand Canyon, Arizona, in March 2013Geology is a branch of natural science concerned with the Earth and other astronomical bodies, the rocks of which they are composed, and the processes by which they change over time. The name comes from Ancient Greek γῆ (gê) 'earth' and λoγία (-logía) 'study of, discourse'.
GuitarThe guitar is a stringed musical instrument that is usually fretted (with some exceptions) and typically has six or twelve strings, though guitars with seven, eight and nine strings also exist. It is usually held flat against the player's body and played by strumming or plucking the strings with the dominant hand, while simultaneously pressing selected strings against frets with the fingers of the opposite hand. A guitar pick may also be used to strike the strings.
TimeTime is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future. Time dictates all forms of action, age, and causality, being a component quantity of various measurements used to sequence events, to compare the duration of events or the intervals between them, and to quantify rates of change of quantities in material reality or in conscious experience.Special:Search/oscillationRelated word or term.*As an Amazon Associate I earn from qualifying purchases.