|
Mirror Images
A mirror image (in a plane mirror) is a reflected duplication of an object that appears almost identical, but is reversed in the direction perpendicular to the mirror surface. As an optical effect it results from reflection off from substances such as a mirror or water. It is also a concept in geometry and can be used as a conceptualization process for 3-D structures. In geometry and geometrical optics In two dimensions In geometry, the mirror image of an object or two-dimensional figure is the virtual image formed by reflection in a plane mirror; it is of the same size as the original object, yet different, unless the object or figure has reflection symmetry (also known as a P-symmetry). Two-dimensional mirror images can be seen in the reflections of mirrors or other reflecting surfaces, or on a printed surface seen inside-out. If we first look at an object that is effectively two-dimensional (such as the writing on a card) and then turn the card to face a mirror, the obje ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Hood Reflected In Mirror Lake, Oregon
Mount is often used as part of the name of specific mountains, e.g. Mount Everest. Mount or Mounts may also refer to: Places * Mount, Cornwall, a village in Warleggan parish, England * Mount, Perranzabuloe, a hamlet in Perranzabuloe parish, Cornwall, England * Mounts, Indiana, a community in Gibson County, Indiana, United States People * Mount (surname) * William L. Mounts (1862–1929), American lawyer and politician Computing and software * Mount (computing), the process of making a file system accessible * Mount (Unix), the utility in Unix-like operating systems which mounts file systems Displays and equipment * Mount, a fixed point for attaching equipment, such as a hardpoint on an airframe * Mounting board, in picture framing * Mount, a hanging scroll for mounting paintings * Mount, to display an item on a heavy backing such as foamcore, e.g.: ** To pin a biological specimen, on a heavy backing in a stretched stable position for ease of dissection or display ** To pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflection Group
In group theory and geometry, a reflection group is a discrete group which is generated by a set of reflections of a finite-dimensional Euclidean space. The symmetry group of a regular polytope or of a tiling of the Euclidean space by congruent copies of a regular polytope is necessarily a reflection group. Reflection groups also include Weyl groups and crystallographic Coxeter groups. While the orthogonal group is generated by reflections (by the Cartan–Dieudonné theorem), it is a continuous group (indeed, Lie group), not a discrete group, and is generally considered separately. Definition Let ''E'' be a finite-dimensional Euclidean space. A finite reflection group is a subgroup of the general linear group of ''E'' which is generated by a set of orthogonal reflections across hyperplanes passing through the origin. An affine reflection group is a discrete subgroup of the affine group of ''E'' that is generated by a set of ''affine reflections'' of ''E'' (without the requi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rear-view Mirror
A rear-view mirror (or rearview mirror) is a flat mirror in automobiles and other vehicles, designed to allow the driver to see rearward through the vehicle's rear window (rear windshield). In cars, the rear-view mirror is usually affixed to the top of the windshield on a double-swivel mount allowing it to be adjusted to suit the height and viewing angle of any driver and to swing harmlessly out of the way if impacted by a vehicle occupant in a collision. The rear-view mirror is augmented by one or more side-view mirrors, which serve as the only rear-vision mirrors on trucks, motorcycles and bicycles. History Among the rear-view mirror's early uses is a mention by Dorothy Levitt in her 1909 book ''The Woman and the Car'' which noted that women should "carry a little hand-mirror in a convenient place when driving" so they may "hold the mirror aloft from time to time in order to see behind while driving in traffic". However, earlier use is described in 1906, in a trad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ambulance
An ambulance is a medically equipped vehicle which transports patients to treatment facilities, such as hospitals. Typically, out-of-hospital medical care is provided to the patient during the transport. Ambulances are used to respond to medical emergencies by emergency medical services (EMS). For this purpose, they are generally equipped with flashing warning lights and sirens. They can rapidly transport paramedics and other first responders to the scene, carry equipment for administering emergency care and transport patients to hospital or other definitive care. Most ambulances use a design based on vans or pickup trucks. Others take the form of motorcycles, buses, limousines, aircraft and boats. Generally, vehicles count as an ambulance if they can transport patients. However, it varies by jurisdiction as to whether a non-emergency patient transport vehicle (also called an ambulette) is counted as an ambulance. These vehicles are not usually (although there are excepti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mirror Writing
Mirror writing is formed by writing in the direction that is the reverse of the natural way for a given language, such that the result is the mirror image of normal writing: it appears normal when it is reflected in a mirror. It is sometimes used as an extremely primitive form of cipher. A common modern usage of mirror writing can be found on the front of ambulances, where the word "AMBULANCE" is often written in very large mirrored text, so that drivers see the word the right way around in their rear-view mirror. Some people are able to produce handwritten mirrored text. Notably, Leonardo da Vinci wrote most of his personal notes in this way. Mirror writing calligraphy was popular in the Ottoman Empire, where it often carried mystical associations. Ability to write mirrored text An informal Australian newspaper experiment identified 10 true mirror-writers in a readership of 65,000. A higher proportion of left-handed people are better mirror writers than right-handed people, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conservation Of Energy
In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be ''conserved'' over time. This law, first proposed and tested by Émilie du Châtelet, means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another. For instance, chemical energy is converted to kinetic energy when a stick of dynamite explodes. If one adds up all forms of energy that were released in the explosion, such as the kinetic energy and potential energy of the pieces, as well as heat and sound, one will get the exact decrease of chemical energy in the combustion of the dynamite. Classically, conservation of energy was distinct from conservation of mass. However, special relativity shows that mass is related to energy and vice versa by ''E = mc2'', and science now takes the view that mass-energy as a whole is conserved. Theoretically, this implies that an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Straight Dope
"The Straight Dope" was a question-and-answer newspaper column written under the pseudonym Cecil Adams. Contributions were made by multiple authors, and it was illustrated (also pseudonymously) by Slug Signorino. It was first published in 1973 in the ''Chicago Reader'' as well as in print syndication nationally in the United States, and on a website with the same name. On more than one occasion, the authors (i.e. Cecil Adams) were forced to retract or modify an answer when confronted by the readers. Following the column of June 27, 2018, the "Straight Dope" column was placed on hiatus, with no decision made regarding its future. The website and associated forum continue to be active. Chicago's public radio station, WBEZ, has purchased Sun-Times Media (STM), which owns the Straight Dope, including the SDMB. Name and tagline The column derives its name from the American idiom meaning roughly "the true information; the full story" and covers many subjects, including history, scienc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binocular Vision
In biology, binocular vision is a type of vision in which an animal has two eyes capable of facing the same direction to perceive a single three-dimensional image of its surroundings. Binocular vision does not typically refer to vision where an animal has eyes on opposite sides of its head and shares no field of view between them, like in some animals. Neurological researcher Manfred Fahle has stated six specific advantages of having two eyes rather than just one: #It gives a creature a "spare eye" in case one is damaged. #It gives a wider field of view. For example, humans have a maximum horizontal field of view of approximately 190 degrees with two eyes, approximately 120 degrees of which makes up the binocular field of view (seen by both eyes) flanked by two uniocular fields (seen by only one eye) of approximately 40 degrees. #It can give stereopsis in which binocular disparity (or parallax) provided by the two eyes' different positions on the head gives precise depth perc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality (mathematics)
In geometry, a figure is chiral (and said to have chirality) if it is not identical to its mirror image, or, more precisely, if it cannot be mapped to its mirror image by rotations and translations alone. An object that is not chiral is said to be ''achiral''. A chiral object and its mirror image are said to be enantiomorphs. The word ''chirality'' is derived from the Greek (cheir), the hand, the most familiar chiral object; the word ''enantiomorph'' stems from the Greek (enantios) 'opposite' + (morphe) 'form'. Examples Some chiral three-dimensional objects, such as the helix, can be assigned a right or left handedness, according to the right-hand rule. Many other familiar objects exhibit the same chiral symmetry of the human body, such as gloves and shoes. Right shoes differ from left shoes only by being mirror images of each other. In contrast thin gloves may not be considered chiral if you can wear them inside-out. The J, L, S and Z-shaped ''tetrominoes'' of the popula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Corballis
Michael Charles Corballis (10 September 1936 – 13 November 2021) was a New Zealand and Canadian psychologist and author. He was Emeritus Professor at the Department of Psychology at the University of Auckland. His fields of research were cognitive psychology and cognitive neuroscience, encompassing visual perception, visual imagery, attention, memory, and the evolution of language. Early life and family Corballis was born in the farming district of Marton, New Zealand, in 1936, the eldest of four sons of sheep farmers Philip Patrick Joseph Corballis and Alice Elizabeth Harris. In 1962, Corballis married Barbara Elizabeth Wheeler; they had two sons: Paul, also a cognitive neuroscientist, and Tim, a novelist and academic. Barbara Corballis died in 2020. Education and career Corballis received his high-school education as a boarder at Wanganui Collegiate School. He earned a Master's degree in Mathematics at the University of New Zealand in 1959 and a Master of Arts in ps ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Normal
In geometry, a normal is an object such as a line, ray, or vector that is perpendicular to a given object. For example, the normal line to a plane curve at a given point is the (infinite) line perpendicular to the tangent line to the curve at the point. A normal vector may have length one (a unit vector) or its length may represent the curvature of the object (a '' curvature vector''); its algebraic sign may indicate sides (interior or exterior). In three dimensions, a surface normal, or simply normal, to a surface at point P is a vector perpendicular to the tangent plane of the surface at P. The word "normal" is also used as an adjective: a line ''normal'' to a plane, the ''normal'' component of a force, the normal vector, etc. The concept of normality generalizes to orthogonality (right angles). The concept has been generalized to differentiable manifolds of arbitrary dimension embedded in a Euclidean space. The normal vector space or normal space of a manifold at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
