Mechanical Engineering, GRA-ION
Mechanical engineering, the branch of engineering concerned with the design, manufacture, installation, and operation of engines and machines and with manufacturing processes. It is particularly concerned with forces and motion.
Mechanical Engineering Encyclopedia Articles By Title
grain size scale, in sedimentology, division of a continuous range of particle sizes into a series of discrete......
gram (g), unit of mass or weight that is used especially in the centimetre-gram-second system of measurement (see......
grapeshot, cannon charge consisting of small round balls, usually of lead or iron, and used primarily as an antipersonnel......
graphics processing unit (GPU), electronic circuit board that can quickly perform many mathematical calculations.......
gravimeter, sensitive device for measuring variations in the Earth’s gravitational field, useful in prospecting......
gray, unit of absorbed dose of ionizing radiation, defined in the 1980s by the International Commission on Radiation......
grease, thick, oily lubricant consisting of inedible lard, the rendered fat of waste animal parts, or a petroleum-derived......
Greek calendar, any of a variety of dating systems used by the several city-states in the time of classical Greece......
Greek fire, any of several flammable compositions that were used in warfare in ancient and medieval times. More......
Greenpeace, international organization dedicated to preserving endangered species of animals, preventing environmental......
Gregorian calendar, solar dating system now in general use. It was proclaimed in 1582 by Pope Gregory XIII as a......
grenade, small explosive, chemical, or gas bomb that is used at short range. The word grenade probably derived......
grey goo, a nightmarish scenario of nanotechnology in which out-of-control self-replicating nanobots destroy the......
grid, in an electron tube, an electrode that has openings for controlling the flow of electrons or ions through......
Edmund Beckett, 1st Baron Grimthorpe was an English lawyer and horologist notorious in his day for his disputatious......
grinding machine, tool that employs a rotating abrasive wheel to change the shape or dimensions of a hard, usually......
ground, in electricity, electrical contact with the Earth, which remains essentially at a constant potential. A......
guided missile, projectile provided with means for altering its direction after leaving its launching device. See...
gun, weapon consisting essentially of a metal tube from which a missile or projectile is shot by the force of exploding......
gun control, politics, legislation, and enforcement of measures intended to restrict access to, the possession......
gunsight, any of numerous optical devices that aid in aiming a firearm. Its forms include the simple iron sights......
Edmund Gunter was an English mathematician who invented many useful measuring devices, including a forerunner of......
halberd, weapon consisting of an ax blade balanced by a pick with an elongated pike head at the end of the staff.......
Stephen Hales was an English botanist, physiologist, and clergyman who pioneered quantitative experimentation in......
half-track, motor vehicle that has wheels in the front and tanklike tracks at the back. Rugged armoured all-terrain......
Edmond Halley was an English astronomer and mathematician who was the first to calculate the orbit of a comet later......
hammer, tool designed for pounding or delivering repeated blows. Varied uses require a multiplicity of designs......
hand, ancient unit of length, now standardized at 4 inches (10.16 cm) and used today primarily for measuring the......
hand tool, any of the implements used by craftspersons in manual operations, such as chopping, chiseling, sawing,......
- Introduction
- Stone, Crafting, Carving
- Limitations, Stone, Tools
- Mousterian, Flake, Tools
- Neolithic, Stone, Flint
- Early Metals, Smelting
- Smelting, Forge, Anvil
- Iron, Steel, Tools
- Hammer, Chisel, Mallet
- Hammers, Mallets, Axes
- European Usage, Crafts, Carpentry
- Drilling, Boring, Chiseling
- Cutting, Shaping, Sharpening
- Types, Uses, History
- Plane, Woodworking, Sharpening
- Tool Auxiliaries, Screws, Drivers
- Screwdrivers, Wrenches, Pliers
- Compass, Divider, Caliper
handgun, any firearm small enough to be held in one hand when fired. It usually fires a single projectile or bullet,......
hank, in textile manufacture, unit of measure applied to a length of yarn or to a loose assemblage of fibres forming......
William Webster Hansen was an American physicist who contributed to the development of radar and is regarded as......
hard-target munition, ammunition capable of damaging and destroying reinforced targets such as tanks and hardened......
Lawrence Hargrave was an English aviation pioneer and inventor of the box kite. Born and educated in England, Hargrave......
James Hargreaves was an English inventor of the spinning jenny, the first practical application of multiple spinning......
Harmonic Drive, mechanical speed-changing device, invented in the 1950s, that reduces the gear ratio of a rotary......
harquebus, first gun fired from the shoulder, a smoothbore matchlock with a stock resembling that of a rifle. The......
Louis Harris was an American public-opinion analyst and columnist who was the best-known pollster in the United......
John Harrison was an English horologist who invented the first practical marine chronometer, which enabled navigators......
harrow, farm implement used to pulverize soil, break up crop residues, uproot weeds, and cover seed. In Neolithic......
Francis Hauksbee, the Elder was a self-educated English scientist and eclectic experimentalist whose discoveries......
Jean de Hautefeuille was a French physicist who built a primitive internal-combustion engine. Born of poor parents,......
hearing aid, device that increases the loudness of sounds in the ear of the wearer. The earliest aid was the ear......
John Heathcoat was a pioneering English inventor of lace-making machinery. One of Heathcoat’s machines (patented......
hectare, unit of area in the metric system equal to 100 ares, or 10,000 square metres, and the equivalent of 2.471......
William Hedley was an English coal-mine official and inventor who built probably the first commercially useful......
Ernst Heinrich Heinkel was a German designer and builder of the first rocket-powered aircraft shortly before the......
henry, unit of either self-inductance or mutual inductance, abbreviated H, and named for the American physicist......
hertz, unit of frequency. The number of hertz (abbreviated Hz) equals the number of cycles per second. The frequency......
William Hewlett was an American engineer and businessman who cofounded the electronics and computer corporation......
Hewlett-Packard Company, American manufacturer of software and computer services and a major brand in the history......
high-voltage electron microscope, type of electron microscope that has been constructed to operate at accelerating......
Hipparchus was a Greek astronomer and mathematician who made fundamental contributions to the advancement of astronomy......
hoe, one of the oldest tools of agriculture, a digging implement consisting of a blade set at a right angle to......
Samuel Kurtz Hoffman was an American propulsion engineer, who led U.S. efforts to develop rocket engines for space......
holography, means of creating a unique photographic image without the use of a lens. The photographic recording......
home appliance, any of numerous and varied electric, electromechanical, or gas-powered devices introduced mainly......
Honeywell International Inc., American advanced-technology company that manufactures aerospace and automotive products;......
horsepower, the common unit of power; i.e., the rate at which work is done. In the British Imperial System, one......
Hotchkiss machine gun, originally a big-bore, hand-cranked, rapid-fire weapon developed in 1878 by Benjamin B.......
hour, in timekeeping, 3,600 seconds, now defined in terms of radiation emitted from atoms of the element cesium......
hourglass, an early device for measuring intervals of time. It is also known as a sandglass or a log glass when......
The law of reflection is fundamental to how mirrors work. When light hits a mirror, it reflects off the surface......
Elias Howe was an American inventor whose sewing machine helped revolutionize garment manufacture in the factory......
Frederick Webster Howe was an American inventor and manufacturer. He was the son of a blacksmith. He produced classic......
Jerome C. Hunsaker was an American aeronautical engineer who made major innovations in the design of aircraft and......
Christiaan Huygens was a Dutch mathematician, astronomer, and physicist, who founded the wave theory of light,......
HVAC, mechanical system used to control the temperature, humidity, and movement of air throughout a building or......
hydraulic transmission, device employing a liquid to transmit and modify linear or rotary motion and linear or......
hydrometer, device for measuring some characteristics of a liquid, such as its density (weight per unit volume)......
hydrophone, device for converting sound waves into electrical signals, similar in operation to a microphone but......
hygrometer, instrument used in meteorological science to measure the humidity, or amount of water vapour in the......
hypsometry, the science of measuring the elevation and depth of features on Earth’s surface with respect to sea......
Hyundai Group, major diversified corporation in South Korea. The international company supplies a product line......
ICBM, Land-based, nuclear-armed ballistic missile with a range of more than 3,500 miles (5,600 km). Only the United......
Idei Nobuyuki is a Japanese business executive who served as chairman (2000–05) and CEO (1999–2005) of the Japanese......
ignition system, in a gasoline engine, means employed for producing an electric spark to ignite the fuel–air mixture;......
ignitron, electron tube functioning as a rectifier to convert alternating current (AC) to direct current (DC).......
Imperial units, units of measurement of the British Imperial System, the traditional system of weights and measures......
improvised explosive device (IED), a homemade bomb, constructed from military or nonmilitary components, that is......
inch, unit of British Imperial and United States Customary measure equal to 136 of a yard. The unit derives from......
inclined plane, simple machine consisting of a sloping surface, used for raising heavy bodies. The force required......
incubator, an insulated enclosure in which temperature, humidity, and other environmental conditions can be regulated......
Indian time zone, time zone in India observing Indian Standard Time (IST)—five and a half hours ahead of Coordinated......
indicator species, organism—often a microorganism or a plant—that serves as a measure of the environmental conditions......
inductance, property of a conductor (often in the shape of a coil) that is measured by the size of the electromotive......
induction coil, an electrical device for producing an intermittent source of high voltage. An induction coil consists......
Industrial Revolution, in modern history, the process of change from an agrarian and handicraft economy to one......
inertial guidance system, electronic system that continuously monitors the position, velocity, and acceleration......
instrumentation, in technology, the development and use of precise measuring equipment. Although the sensory organs......
integrated circuit (IC), an assembly of electronic components, fabricated as a single unit, in which miniaturized......
intercalation, insertion of days or months into a calendar to bring it into line with the solar year (year of the......
intermediate-range nuclear weapons, Class of nuclear weapons with a range of 620–3,400 mi (1,000–5,500 km). Some......
internal-combustion engine, any of a group of devices in which the reactants of combustion (oxidizer and fuel)......
International Bureau of Weights and Measures (BIPM), international organization founded to bring about the unification......
International Date Line, imaginary line extending between the North Pole and the South Pole and arbitrarily demarcating......
International System of Units (SI), international decimal system of weights and measures derived from and extending......
International Unit (IU), in pharmacology, quantity of a substance, such as a vitamin, hormone, or toxin, that produces......
Intertype, (trademark), typesetting machine similar to Linotype that sets type in full lines called slugs, long......
ionization chamber, radiation detector used for determining the intensity of a beam of radiation or for counting......