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The Taiwan Beer Leopards ( Chinese: 台啤永豐雲豹) are a Taiwanese professional basketball team based in Taoyuan City. They have competed in the T1 League since the 2021–22 season, and play their home games at the Taoyuan Arena. The Leopards became one of the six teams of the inaugural T1 League season. On July 4, 2023, the Taoyuan ...
Renewable energy (or green energy, low-carbon energy) is energy from renewable natural resources that are replenished on a human timescale. Using renewable energy technologies helps with climate change mitigation, energy security, and also has some economic benefits.[1] Commonly used renewable energy types include solar energy, wind power ...
Leucippus was a Greek philosopher of the 5th century BCE. He is credited with founding atomism, with his student Democritus. Leucippus divided the world into two entities: atoms, indivisible particles that make up all things, and the void, the nothingness between the atoms. Leucippus's ideas were influential in ancient and Renaissance philosophy.
Enron scandal. The Enron scandal was an accounting scandal involving Enron Corporation, an American energy company based in Houston, Texas. When news of widespread fraud within the company became public in October 2001, the company declared bankruptcy and its accounting firm, Arthur Andersen – then one of the five largest audit and ...
- Forms
- History
- Units of Measure
- Scientific Use
- Transformation
- Conservation of Energy
- Energy Transfer
- Thermodynamics
- See Also
- Further Reading
The total energy of a system can be subdivided and classified into potential energy, kinetic energy, or combinations of the two in various ways. Kinetic energy is determined by the movement of an object – or the composite motion of the object's components – while potential energy reflects the potential of an object to have motion, generally being b...
The word energy derives from the Ancient Greek: ἐνέργεια, romanized: energeia, lit. 'activity, operation', which possibly appears for the first time in the work of Aristotlein the 4th century BC. In contrast to the modern definition, energeia was a qualitative philosophical concept, broad enough to include ideas such as happiness and pleasure. In t...
In 1843, James Prescott Joule independently discovered the mechanical equivalent in a series of experiments. The most famous of them used the "Joule apparatus": a descending weight, attached to a string, caused rotation of a paddle immersed in water, practically insulated from heat transfer. It showed that the gravitational potential energy lost by...
Classical mechanics
In classical mechanics, energy is a conceptually and mathematically useful property, as it is a conserved quantity. Several formulations of mechanics have been developed using energy as a core concept. Work, a function of energy, is force times distance. 1. W = ∫ C F ⋅ d s {\displaystyle W=\int _{C}\mathbf {F} \cdot \mathrm {d} \mathbf {s} } This says that the work (W {\displaystyle W} ) is equal to the line integral of the force F along a path C; for details see the mechanical work article....
Chemistry
In the context of chemistry, energy is an attribute of a substance as a consequence of its atomic, molecular, or aggregate structure. Since a chemical transformation is accompanied by a change in one or more of these kinds of structure, it is usually accompanied by a decrease, and sometimes an increase, of the total energy of the substances involved. Some energy may be transferred between the surroundings and the reactants in the form of heat or light; thus the products of a reaction have som...
Biology
In biology, energy is an attribute of all biological systems, from the biosphere to the smallest living organism. Within an organism it is responsible for growth and development of a biological cell or organelle of a biological organism. Energy used in respiration is stored in substances such as carbohydrates (including sugars), lipids, and proteins stored by cells. In human terms, the human equivalent (H-e) (Human energy conversion) indicates, for a given amount of energy expenditure, the re...
Energy may be transformed between different forms at various efficiencies. Items that transform between these forms are called transducers. Examples of transducers include a battery (from chemical energy to electric energy), a dam (from gravitational potential energy to kinetic energy of moving water (and the blades of a turbine) and ultimately to ...
The fact that energy can be neither created nor destroyed is called the law of conservation of energy. In the form of the first law of thermodynamics, this states that a closed system's energy is constant unless energy is transferred in or out as work or heat, and that no energy is lost in transfer. The total inflow of energy into a system must equ...
Closed systems
Energy transfer can be considered for the special case of systems which are closed to transfers of matter. The portion of the energy which is transferred by conservative forces over a distance is measured as the work the source system does on the receiving system. The portion of the energy which does not do work during the transfer is called heat.[note 3] Energy can be transferred between systems in a variety of ways. Examples include the transmission of electromagnetic energy via photons, ph...
Open systems
Beyond the constraints of closed systems, open systems can gain or lose energy in association with matter transfer (this process is illustrated by injection of an air-fuel mixture into a car engine, a system which gains in energy thereby, without addition of either work or heat). Denoting this energy by E matter {\displaystyle E_{\text{matter}}} , one may write
Internal energy
Internal energyis the sum of all microscopic forms of energy of a system. It is the energy needed to create the system. It is related to the potential energy, e.g., molecular structure, crystal structure, and other geometric aspects, as well as the motion of the particles, in form of kinetic energy. Thermodynamics is chiefly concerned with changes in internal energy and not its absolute value, which is impossible to determine with thermodynamics alone.
First law of thermodynamics
The first law of thermodynamics asserts that the total energy of a system and its surroundings (but not necessarily thermodynamic free energy) is always conserved and that heat flow is a form of energy transfer. For homogeneous systems, with a well-defined temperature and pressure, a commonly used corollary of the first law is that, for a system subject only to pressure forces and heat transfer (e.g., a cylinder-full of gas) without chemical changes, the differential change in the internal en...
Equipartition of energy
The energy of a mechanical harmonic oscillator (a mass on a spring) is alternately kinetic and potential energy. At two points in the oscillation cycle it is entirely kinetic, and at two points it is entirely potential. Over a whole cycle, or over many cycles, average energy is equally split between kinetic and potential. This is an example of the equipartition principle: the total energy of a system with many degrees of freedom is equally split among all available degrees of freedom, on aver...
Journals
1. The Journal of Energy History / Revue d'histoire de l'énergie(JEHRHE), 2018–
Neil Alden Armstrong (August 5, 1930 – August 25, 2012) was an American astronaut and aeronautical engineer who in 1969 became the first person to walk on the Moon. He was also a naval aviator, test pilot, and university professor. Armstrong was born and raised in Wapakoneta, Ohio. He entered Purdue University, studying aeronautical ...
Sundar Pichai. Pichai Sundararajan (born June 10, 1972 [3] [4] [5] ), better known as Sundar Pichai ( / ˈsʊndɑːr pɪˈtʃaɪ / ), is an Indian-born American business executive. [6] [7] He is the chief executive officer (CEO) of Alphabet Inc. and its subsidiary Google. [8] Pichai began his career as a materials engineer.
