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In physics, electromagnetism is an interaction that occurs between particles with electric charge via electromagnetic fields. The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electrostatics and magnetism, two distinct but closely intertwined phenomena. Electromagnetic forces occur between any two charged particles, causing an attraction between particles with opposite charges and repulsion between particles with the same charge, while magnetism is an interaction that occurs exclusively between charged particles in relative motion. These two effects combine to create electromagnetic fields in the vicinity of charged particles, which can accelerate other charged particles via the Lorentz force. At high energy, the weak force and electromagnetic force are unified as a single electroweak force.
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.
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Adamant in classical mythology is an archaic form of diamond. In fact, the English word diamond is ultimately derived from adamas, via Late Latin diamas and Old French diamant. In ancient Greek ἀδάμας, genitive ἀδάμαντος, literally 'unconquerable, untameable'. In those days, the qualities of hard metal were attributed to it, and adamant became as a result an independent concept.
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William Gilbert, also known as Gilberd, was an English physician, physicist and natural philosopher. He passionately rejected both the prevailing Aristotelian philosophy and the Scholastic method of university teaching. He is remembered today largely for his book De Magnete (1600).
In physics, a moment is a mathematical expression involving the product of a force and perpendicular distance from the point of action of the force. Moments are usually defined with respect to a fixed reference point and refer to physical quantities located some distance from the reference point. In this way, the moment accounts for the quantity's location or arrangement. For example, the moment of force, often called torque, is the product of a force on an object and the distance from the reference point to the object. In principle, any physical quantity can be multiplied by a distance to produce a moment. Commonly used quantities include forces, masses, and electric charge distributions.
Electric power is the transfer of electrical energy within a circuit. Its SI unit is the watt, the general unit of power, defined as one joule per second. Standard prefixes apply to watts as with other SI units: thousands, millions and billions of watts are called kilowatts, megawatts and gigawatts respectively.
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The history of electromagnetic theory begins with ancient measures to understand atmospheric electricity, in particular lightning. People then had little understanding of electricity, and were unable to explain the phenomena. Scientific understanding into the nature of electricity grew throughout the eighteenth and nineteenth centuries through the work of researchers such as Coulomb, Ampère, Faraday and Maxwell.
Coulomb's inverse-square law, or simply Coulomb's law, is an experimental law of physics that calculates the amount of force between two electrically charged particles at rest. This electric force is conventionally called electrostatic force or Coulomb force. Although the law was known earlier, it was first published in 1785 by French physicist Charles-Augustin de Coulomb. Coulomb's law was essential to the development of the theory of electromagnetism and maybe even its starting point, as it allowed meaningful discussions of the amount of electric charge in a particle.
Statary is a term currently applied in fields such as ecology, ethology, psychology. In modern use it contrasts on the one hand with such concepts as migratory, nomadic, or shifting, and on the other with static or immobile. The word also is of historical interest in its change of meaning as its usage changed.
This glossary of physics is a list of definitions of terms and concepts relevant to physics, its sub-disciplines, and related fields, including mechanics, materials science, nuclear physics, particle physics, and thermodynamics. For more inclusive glossaries concerning related fields of science and technology, see Glossary of chemistry terms, Glossary of astronomy, Glossary of areas of mathematics, and Glossary of engineering.
References
- 1 2 electric, adj. and n., Oxford English Dictionary, Draft Revision Mar. 2008
- ↑ Bacon F, "Physiological Remains", before 1626, in Baconiana (1679)
- ↑ Equivalent text in Pseudodoxia Epidemica, 6th edition (1672), p. 53
- 1 2 Niels H. de V. Heathcote (December 1967). "The early meaning of electricity: Some Pseudodoxia Epidemica - I". Annals of Science. 23 (4): 261–275. doi:10.1080/00033796700203316.
- ↑ "electric". Webster's 1913. Retrieved 2022-12-27.
- ↑ "Electricity". Websters Dictionary 1828. Retrieved 2022-12-27.
- ↑ "electricity". Webster's 1913. Retrieved 2022-12-27.
- ↑ "charge | Etymology, origin and meaning". etymonline. Retrieved 2022-12-27.