|
Statohm
The statohm (symbol: statΩ) is the unit of electrical resistance in the electrostatic system of units which was part of the CGS system of units based upon the centimetre, gram and second. The static units in that system are related to the corresponding electromagnetic units by a factor of the speed of light. Those units are known as absolute units, and so the counterpart of the statohm is the abohm (abΩ), and their proportions are: 1 statΩ ≘ ''c''2 abΩ ≈ abΩ where ''c'' is the speed of light in centimetres per second. These units are not common now. The SI unit of resistance is the ohm (Ω). The statohm is nearly a trillion ''Trillion'' is a number with two distinct definitions: *1,000,000,000,000, i.e. one million 1,000,000, million, or (ten to the twelfth Exponentiation, power), as defined on the long and short scales, short scale. This is now the meaning in bot ... times larger than the ohm and is the largest unit of resistance ever used in any measurement s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Resistance
The electrical resistance of an object is a measure of its opposition to the flow of electric current. Its reciprocal quantity is , measuring the ease with which an electric current passes. Electrical resistance shares some conceptual parallels with mechanical friction. The SI unit of electrical resistance is the ohm (), while electrical conductance is measured in siemens (S) (formerly called the 'mho' and then represented by ). The resistance of an object depends in large part on the material it is made of. Objects made of electrical insulators like rubber tend to have very high resistance and low conductance, while objects made of electrical conductors like metals tend to have very low resistance and high conductance. This relationship is quantified by resistivity or conductivity. The nature of a material is not the only factor in resistance and conductance, however; it also depends on the size and shape of an object because these properties are extensive rather tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrostatic Units
Electrostatics is a branch of physics that studies slow-moving or stationary electric charges. Since classical times, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word (), meaning 'amber', was thus the root of the word ''electricity''. Electrostatic phenomena arise from the forces that electric charges exert on each other. Such forces are described by Coulomb's law. There are many examples of electrostatic phenomena, from those as simple as the attraction of plastic wrap to one's hand after it is removed from a package, to the apparently spontaneous explosion of grain silos, the damage of electronic components during manufacturing, and photocopier and laser printer operation. The electrostatic model accurately predicts electrical phenomena in "classical" cases where the velocities are low and the system is macroscopic so no quantum effects are involved. It also plays a role in quantum mechanics, where addition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centimetre–gram–second System Of Units
The centimetre–gram–second system of units (CGS or cgs) is a variant of the metric system based on the centimetre as the unit of length, the gram as the unit of mass, and the second as the unit of time. All CGS mechanical units are unambiguously derived from these three base units, but there are several different ways in which the CGS system was extended to cover electromagnetism. The CGS system has been largely supplanted by the MKS system based on the metre, kilogram, and second, which was in turn extended and replaced by the International System of Units (SI). In many fields of science and engineering, SI is the only system of units in use, but CGS is still prevalent in certain subfields. In measurements of purely mechanical systems (involving units of length, mass, force, energy, pressure, and so on), the differences between CGS and SI are straightforward: the unit-conversion factors are all powers of 10 as and . For example, the CGS unit of force is the dyne, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Of Light
The speed of light in vacuum, commonly denoted , is a universal physical constant exactly equal to ). It is exact because, by international agreement, a metre is defined as the length of the path travelled by light in vacuum during a time interval of second. The speed of light is invariant (physics), the same for all observers, no matter their relative velocity. It is the upper limit for the speed at which Information#Physics_and_determinacy, information, matter, or energy can travel through Space#Relativity, space. All forms of electromagnetic radiation, including visible light, travel at the speed of light. For many practical purposes, light and other electromagnetic waves will appear to propagate instantaneously, but for long distances and sensitive measurements, their finite speed has noticeable effects. Much starlight viewed on Earth is from the distant past, allowing humans to study the history of the universe by viewing distant objects. When Data communication, comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abohm
The abohm is the derived unit of electrical resistance in the emu-cgs ''(centimeter-gram-second)'' system of units (emu stands for "electromagnetic units"). One abohm corresponds to 10−9 ohms in the SI system of units, which is a nanoohm. The emu-cgs (or "electromagnetic cgs") units are one of several systems of electromagnetic units within the centimetre gram second system of units; others include esu-cgs, Gaussian units, and Heaviside–Lorentz units. In these other systems, the abohm is ''not'' one of the units. When a current of one abampere (1 abA) flows through a resistance of 1 abohm, the resulting potential difference across the component is one abvolt (1 abV). The name abohm was introduced by Kennelly in 1903 as a short name for the long name ''(absolute) electromagnetic cgs unit of resistance'' that was in use since the adoption of the cgs system in 1875.A.E. Kennelly (1903"Magnetic units and other subjects that might occupy attention at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SI Unit
The International System of Units, internationally known by the abbreviation SI (from French ), is the modern form of the metric system and the world's most widely used system of units of measurement, system of measurement. It is the only system of measurement with official status in nearly every country in the world, employed in science, technology, industry, and everyday commerce. The SI system is coordinated by the International Bureau of Weights and Measures, which is abbreviated BIPM from . The SI comprises a coherence (units of measurement), coherent system of unit of measurement, units of measurement starting with seven SI base unit, base units, which are the second (symbol s, the unit of time), metre (m, length), kilogram (kg, mass), ampere (A, electric current), kelvin (K, thermodynamic temperature), mole (unit), mole (mol, amount of substance), and candela (cd, luminous intensity). The system can accommodate coherent units for an unlimited number of additional quantiti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orders Of Magnitude (numbers)
This list contains selected positive numbers in increasing order, including counts of things, dimensionless quantities and probabilities. Each number is given a name in the short scale, which is used in English-speaking countries, as well as a name in the long scale, which is used in some of the countries that do not have English as their national language. Smaller than (one googolth) * ''Physics:'' The probability of a human spontaneously teleporting due to quantum effects is approximately 10−4.5×1029. * ''Mathematics – random selections:'' Approximately is a rough first estimate of the probability that a typing "monkey", or an English-illiterate typing robot, when placed in front of a typewriter, will type out William Shakespeare's play ''Hamlet'' as its first set of inputs, on the precondition it typed the needed number of characters. However, demanding correct punctuation, capitalization, and spacing, the probability falls to around 10−360,783. * ''Comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Electrical Resistance
Unit may refer to: General measurement * Unit of measurement, a definite magnitude of a physical quantity, defined and adopted by convention or by law **International System of Units (SI), modern form of the metric system **English units, historical units of measurement used in England up to 1824 **Unit of length Science and technology Physical sciences * Natural unit, a physical unit of measurement * Geological unit or rock unit, a volume of identifiable rock or ice * Astronomical unit, a unit of length roughly between the Earth and the Sun Chemistry and medicine * Equivalent (chemistry), a unit of measurement used in chemistry and biology * Unit, a vessel or section of a chemical plant * Blood unit, a measurement in blood transfusion * Enzyme unit, a measurement of active enzyme in a sample * International unit, a unit of measurement for nutrients and drugs Mathematics * Unit number, the number 1 * Unit, identity element * Unit (ring theory), an element that is inverti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
