|
Magnetic Compass
A compass is a device that shows the cardinal directions used for navigation and geographic orientation. It commonly consists of a magnetized needle or other element, such as a compass card or compass rose, which can pivot to align itself with magnetic north. Other methods may be used, including gyroscopes, magnetometers, and GPS receivers. Compasses often show angles in degrees: north corresponds to 0°, and the angles increase clockwise, so east is 90°, south is 180°, and west is 270°. These numbers allow the compass to show azimuths or bearings which are commonly stated in degrees. If local variation between magnetic north and true north is known, then direction of magnetic north also gives direction of true north. Among the Four Great Inventions, the magnetic compass was first invented as a device for divination as early as the history of science and technology in China, Chinese Han dynasty (since c. 206 BC),#Li, Li Shu-hua, p. 176 and later adopted for navigation by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2016 Busola
Sixteen or 16 may refer to: *16 (number) *one of the years 16 BC, AD 16, 1916, 2016 Films * ''Pathinaaru'' or ''Sixteen'', a 2010 Tamil film * ''Sixteen'' (1943 film), a 1943 Argentine film directed by Carlos Hugo Christensen * Sixteen (2013 Indian film), ''Sixteen'' (2013 Indian film), a 2013 Hindi film * Sixteen (2013 British film), ''Sixteen'' (2013 British film), a 2013 British film by director Rob Brown Music *The Sixteen, an English choir *16 (band), a sludge metal band *Sixteen (Polish band), a Polish band Albums *16 (Robin album), ''16'' (Robin album), a 2014 album by Robin * 16 (Madhouse album), a 1987 album by Madhouse *Sixteen (album), ''Sixteen'' (album), a 1983 album by Stacy Lattisaw *''Sixteen'' , a 2005 album by Shook Ones (band), Shook Ones * ''16'', a 2020 album by Wejdene Songs *16 (Sneaky Sound System song), "16" (Sneaky Sound System song), 2009 *Sixteen (Thomas Rhett song), "Sixteen" (Thomas Rhett song), 2017 *Sixteen (Ellie Goulding song), "Sixteen" (Elli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Europe
Western Europe is the western region of Europe. The region's extent varies depending on context. The concept of "the West" appeared in Europe in juxtaposition to "the East" and originally applied to the Western half of the ancient Mediterranean world, the Latin West of the Roman Empire, and "Western Christendom". Beginning with the Renaissance and the Age of Discovery, roughly from the 15th century, the concept of ''Europe'' as "the Western world, West" slowly became distinguished from and eventually replaced the dominant use of "Christendom" as the preferred endonym within the area. By the Age of Enlightenment and the Industrial Revolution, the concepts of "Eastern Europe" and "Western Europe" were more regularly used. The distinctiveness of Western Europe became most apparent during the Cold War, when Europe was divided for 40 years by the Iron Curtain into the Western Bloc and Eastern Bloc, each characterised by distinct political and economical systems. Historical divisions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnet
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets. A permanent magnet is an object made from a material that is magnetized and creates its own persistent magnetic field. An everyday example is a refrigerator magnet used to hold notes on a refrigerator door. Materials that can be magnetized, which are also the ones that are strongly attracted to a magnet, are called ferromagnetic (or ferrimagnetic). These include the elements iron, nickel and cobalt and their alloys, some alloys of rare-earth metals, and some naturally occurring minerals such as lodestone. Although ferromagnetic (and ferrimagnetic) materials are the only ones attracted to a magnet strongly enough to be commonly considered magnetic, all other substances respond weakly to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thales Of Miletus
Thales of Miletus ( ; ; ) was an Ancient Greek pre-Socratic philosopher from Miletus in Ionia, Asia Minor. Thales was one of the Seven Sages, founding figures of Ancient Greece. Beginning in eighteenth-century historiography, many came to regard him as the first philosopher in the Greek tradition, breaking from the prior use of mythology to explain the world and instead using natural philosophy. He is thus otherwise referred to as the first to have engaged in mathematics, science, and deductive reasoning. Thales's view that all of nature is based on the existence of a single ultimate substance, which he theorized to be water, was widely influential among the philosophers of his time. Thales thought the Earth floated on water. In mathematics, Thales is the namesake of Thales's theorem, and the intercept theorem can also be referred to as Thales's theorem. Thales was said to have calculated the heights of the pyramids and the distance of ships from the shore. In scien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomagnetic Secular Variation
Geomagnetic secular variation is the changes in the Earth's magnetic field on time scales of about a year or more. These changes mostly reflect changes in the Earth's interior, while more rapid changes mostly originate in the ionosphere or magnetosphere. The geomagnetic field changes on time scales from milliseconds to millions of years. Shorter time scales mostly arise from currents in the ionosphere and magnetosphere, and some changes can be traced to geomagnetic storms or daily variations in currents. Changes over time scales of a year or more mostly reflect changes in the Earth's interior, particularly the iron-rich core. These changes are referred to as '' secular variation''. In most models, the secular variation is the amortized time derivative of the magnetic field \mathbf, \dot. The second derivative, \ddot is the ''secular acceleration''. Recent changes Secular variation can be observed in measurements at magnetic observatories, some of which have been operating f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic North
The north magnetic pole, also known as the magnetic north pole, is a point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downward (in other words, if a magnetic compass needle is allowed to rotate in three dimensions, it will point straight down). There is only one location where this occurs, near (but distinct from) the geographic north pole. The Earth's Magnetic North Pole is actually considered the "south pole" in terms of a typical magnet, meaning that the north pole of a magnet would be attracted to the Earth's magnetic north pole. The north magnetic pole moves over time according to magnetic changes and flux lobe elongation in the Earth's outer core. In 2001, it was determined by the Geological Survey of Canada to lie west of Ellesmere Island in northern Canada at . It was situated at in 2005. In 2009, while still situated within the Canadian Arctic at , it was moving toward Russia at between per year. In 2013, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographical North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. It is called the True North Pole to distinguish from the Magnetic North Pole. The North Pole is by definition the northernmost point on the Earth, lying antipodally to the South Pole. It defines geodetic latitude 90° North, as well as the direction of true north. At the North Pole all directions point south; all lines of longitude converge there, so its longitude can be defined as any degree value. No time zone has been assigned to the North Pole, so any time can be used as the local time. Along tight latitude circles, counterclockwise is east and clockwise is west. The North Pole is at the center of the Northern Hemisphere. The nearest land is usually said to be Kaffeklubben Island, off the northern coast of Greenland about away, though some perhaps semi-permanent gravel banks lie slightly clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jewel Bearing
A jewel bearing is a plain bearing in which a metal spindle (tool), spindle turns in a gemstone, jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewels are typically made from the mineral corundum, usually either synthetic sapphire or Ruby#Synthesis and imitation, synthetic ruby. Jewel bearings are used in precision instruments where low friction, long life, and dimensional accuracy are important. Their main use is in mechanical watches. History Jewel bearings were invented in 1704 for use in watches by Nicolas Fatio de Duillier, Peter Debaufre, and Jacob Debaufre, who received an English patent for the idea. Originally natural jewels were used, such as diamond, sapphire, ruby, and garnet. In 1902, Verneuil process, a process to make synthetic sapphire and ruby (crystalline aluminium oxide, also known as corundum) was invented by Auguste Verneuil, making jewelled bearings much cheaper. Today most jewelled ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torque
In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. When being referred to as moment of force, it is commonly denoted by . Just as a linear force is a push or a pull applied to a body, a torque can be thought of as a twist applied to an object with respect to a chosen point; for example, driving a screw uses torque to force it into an object, which is applied by the screwdriver rotating around its axis to the drives on the head. Historical terminology The term ''torque'' (from Latin , 'to twist') is said to have been suggested by James Thomson and appeared in print in April, 1884. Usage is attested the same year by Silvanus P. Thompson in the first edition of ''Dynamo-Electric Machinery''. Thompson describes his usage of the term as follows: Today, torque is referred to using d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Field
A magnetic field (sometimes called B-field) is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to the magnetic field. A permanent magnet's magnetic field pulls on ferromagnetic materials such as iron, and attracts or repels other magnets. In addition, a nonuniform magnetic field exerts minuscule forces on "nonmagnetic" materials by three other magnetic effects: paramagnetism, diamagnetism, and antiferromagnetism, although these forces are usually so small they can only be detected by laboratory equipment. Magnetic fields surround magnetized materials, electric currents, and electric fields varying in time. Since both strength and direction of a magnetic field may vary with location, it is described mathematically by a function (mathematics), function assigning a Euclidean vector, vector to each point of space, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth's Magnetic Field
Earth's magnetic field, also known as the geomagnetic field, is the magnetic field that extends from structure of Earth, Earth's interior out into space, where it interacts with the solar wind, a stream of charged particles emanating from the Sun. The magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo. The magnitude of Earth's magnetic field at its surface ranges from . As an approximation, it is represented by a field of a magnetic dipole currently tilted at an angle of about 11° with respect to Earth's rotational axis, as if there were an enormous bar magnet placed at that angle through the center of Earth. The North geomagnetic pole (Ellesmere Island, Nunavut, Canada) actually represents the South pole of Earth's magnetic field, and conversely the South geomagnetic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
