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Orders Of Magnitude (force) ...
The following list shows different orders of magnitude of force. Since weight under gravity is a force, several of these examples refer to the weight of various objects. Unless otherwise stated, these are weights under average Earth gravity at sea level. Below 1 N 1 N and above Notes External links {{DEFAULTSORT:Orders Of Magnitude (Force) Force In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Force Examples
In physics, a force is an influence that can change the motion of an object. A force can cause an object with mass to change its velocity (e.g. moving from a state of rest), i.e., to accelerate. Force can also be described intuitively as a push or a pull. A force has both magnitude and direction, making it a vector quantity. It is measured in the SI unit of newton (N). Force is represented by the symbol (formerly ). The original form of Newton's second law states that the net force acting upon an object is equal to the rate at which its momentum changes with time. If the mass of the object is constant, this law implies that the acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object. Concepts related to force include: thrust, which increases the velocity of an object; drag, which decreases the velocity of an object; and torque, which produce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FEEP
Field-emission electric propulsion (FEEP) is an advanced electrostatic space propulsion concept, a form of ion thruster, that uses a liquid metal as a propellant – usually either caesium, indium, or mercury. A FEEP device consists of an emitter and an accelerator electrode. A potential difference of the order of 10 kV is applied between the two, which generates a strong electric field at the tip of the metal surface. The interplay of electric force and the liquid metal’s surface tension generates surface instabilities, which give rise to Taylor cones on the liquid surface. At sufficiently high values of the applied field, ions are extracted from the cone tip by field evaporation or similar mechanisms, which then are electrically accelerated to high velocities – typically 100 km/s or more. Due to its very low thrust (in the micronewton (μN) to millinewton (mN) range), FEEP thrusters are primarily used for microradian, micronewton attitude control on spacecraft, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Alligator
The American alligator (''Alligator mississippiensis''), sometimes referred to colloquially as a gator or common alligator, is a large crocodilian reptile native to the Southeastern United States. It is one of the two extant species in the genus ''Alligator'', and is larger than the only other living alligator species, the Chinese alligator. Adult male American alligators measure in length, and can weigh up to , with unverified sizes of up to and weights of making it one of the largest members of the family Alligatoridae, alongside the black caiman. Females are smaller, measuring in length. The American alligator inhabits subtropical and tropical freshwater wetlands, such as marshes and cypress swamps, from southern Texas to North Carolina. It is distinguished from the sympatric American crocodile by its broader snout, with overlapping jaws and darker coloration, and is less tolerant of saltwater but more tolerant of cooler climates than the American crocodile, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clean And Jerk
The clean and jerk is a composite of two weightlifting movements, most often performed with a barbell: the clean and the jerk. During the ''clean'', the lifter moves the barbell from the floor to a racked position across the deltoids, without resting fully on the clavicles. During the ''jerk'', the lifter raises the barbell to a stationary position above the head, finishing with straight arms and legs, and the feet in the same plane as the torso and barbell. Of the several variants of the lift, the most common is the Olympic clean and jerk, which, with the snatch, is contested in Olympic weightlifting events. Clean To execute a ''clean'', a lifter grasps the barbell just outside the legs, typically using a hook grip. Once the barbell is above the knees, the lifter extends explosively (mainly at torso or genitals), raising the bar as high as possible before quickly dropping into a squat and receiving it in a "racked" position in front of the neck and resting on the shoulders. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olympic Weightlifting
Olympic weightlifting, or Olympic-style weightlifting (officially named Weightlifting), is a sport in which athletes compete in lifting a barbell loaded with weight plates from the ground to overhead, with each athlete trying to successfully lift the heaviest weights. Athletes compete in two specific ways of lifting the barbell overhead: these are the snatch and the clean and jerk. The ''snatch'' is a wide-grip lift, in which the weighted barbell is lifted overhead in one motion. The ''clean and jerk'' is a combination lift, in which the weight is first taken from the ground to the front of the shoulders (the clean), and then from the shoulders to overhead (the jerk). The clean and press, wherein a clean was followed by an overhead press, was formerly also a competition lift, but was discontinued due to difficulties in judging proper form. Each weightlifter gets three attempts at both the snatch and the clean and jerk, with the snatch attempts being done first. An athlete's sco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilonewton
The newton (symbol: N) is the unit of force in the International System of Units (SI). It is defined as 1 kg⋅m/s, the force which gives a mass of 1 kilogram an acceleration of 1 metre per second per second. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. Definition A newton is defined as 1 kg⋅m/s (it is a derived unit which is defined in terms of the SI base units). One newton is therefore the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force. The units "metre per second squared" can be understood as measuring a rate of change in velocity per unit of time, i.e. an increase in velocity by 1 metre per second every second. In 1946, Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilogram-force
The kilogram-force (kgf or kgF), or kilopond (kp, from la, pondus, lit=weight), is a non-standard gravitational metric unit of force. It does not comply with the International System of Units (SI) and is deprecated for most uses. The kilogram-force is equal to the magnitude of the force exerted on one kilogram of mass in a gravitational field (standard gravity, a conventional value approximating the average magnitude of gravity on Earth). That is, it is the weight of a kilogram under standard gravity. Therefore, one kilogram-force is by definition equal to .NISTbr>''Guide for the Use of the International System of Units (SI)''Special Publication 811, (1995) page 51 Similarly, a gram-force is , and a milligram-force is . Kilogram-force is a non-standard unit and is classified in the International System of Units (SI) as a unit that is not accepted for use with SI. History The gram-force and kilogram-force were never well-defined units until the CGPM adopted a ''standard accele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dual-Stage 4-Grid
The Dual-Stage 4-Grid (DS4G) is an electrostatic ion thruster design developed by the European Space Agency, in collaboration with the Australian National University. The design was derived by D. Fern from Controlled Thermonuclear Reactor experiments that use a 4-grid mechanism to accelerate ion beams. A 4-grid ion thruster with only 0.2 m diameter is projected to absorb 250 kW power. With that energy input rate, the thruster could produce a thrust of 2.5 N. The specific impulse (a measure of fuel efficiency), could reach 19,300 s at an exhaust velocity of 210 km/s if xenon propellant was used. THE INNOVATIVE DUAL-STAGE 4-GRID ION THRUSTER CONCEPT – THEORY AND EXPERIMENTAL RESULTS The potentially attainable power and thrust densities would substantially extend the power absorption of current ion thrusters to fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smartphone
A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, which facilitate wider software, internet (including web browsing over mobile broadband), and multimedia functionality (including music, video, cameras, and gaming), alongside core phone functions such as voice calls and text messaging. Smartphones typically contain a number of metal–oxide–semiconductor (MOS) integrated circuit (IC) chips, include various sensors that can be leveraged by pre-included and third-party software (such as a magnetometer, proximity sensors, barometer, gyroscope, accelerometer and more), and support wireless communications protocols (such as Bluetooth, Wi-Fi, or satellite navigation). Early smartphones were marketed primarily towards the enterprise market, attempting to bridge the functionality of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Space 1
''Deep Space 1'' (DS1) was a NASA technology demonstration spacecraft which flew by an asteroid and a comet. It was part of the New Millennium Program, dedicated to testing advanced technologies. Launched on 24 October 1998, the ''Deep Space 1'' spacecraft carried out a flyby of asteroid 9969 Braille, which was its primary science target. The mission was extended twice to include an encounter with comet 19P/Borrelly and further engineering testing. Problems during its initial stages and with its star tracker led to repeated changes in mission configuration. While the flyby of the asteroid was only a partial success, the encounter with the comet retrieved valuable information. The Deep Space series was continued by the ''Deep Space 2'' probes, which were launched in January 1999 piggybacked on the Mars Polar Lander and were intended to strike the surface of Mars (though contact was lost and the mission failed). ''Deep Space 1'' was the first NASA spacecraft to use ion thruster, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Thruster
An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. It creates thrust by accelerating ions using electricity. An ion thruster ionizes a neutral gas by extracting some electrons out of atoms, creating a cloud of positive ions. Ion thrusters are categorized as either electrostatic or electromagnetic. Electrostatic thruster ions are accelerated by the Coulomb force along the electric field direction. Temporarily stored electrons are reinjected by a ''neutralizer'' in the cloud of ions after it has passed through the electrostatic grid, so the gas becomes neutral again and can freely disperse in space without any further electrical interaction with the thruster. By contrast, electromagnetic thruster ions are accelerated by the Lorentz force to accelerate all species (free electrons as well as positive and negative ions) in the same direction whatever their electric charge, and are specifically referred to as plasma prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
