Ge

Ge

Germanium is a silvery white brittle metalloid member of the carbon group of elements. Its physical properties being similar to those of silicon.

Gear Design

Fundamental parameters used in describing gears.

Gear Mesh Frequency

A potential vibration frequency on any machine that contains gears; equal to the number of teeth multiplied by the rotational frequency of the gear.

Gear Noise

Gear noise such as whine are generated by meshing gears due to the vibration caused by failure of the rolling action between the mating teeth.

Gearbox

A mechanical device that provides a torque-speed conversion between an input and output shaft.

Gears

Wheels with teeth around the circumference that mesh to transfer rotation between the two at the ratio of the radius of the pitch circle.

Geiger Counter

A radiation detector consisting of two electrodes with a low-pressure gas in between.

Geiger, Johannes

Helped to develop first successful counter of alpha particles.

Gene

Part of a chromosome found inside the cells of living organisms.

General

Lists all General topics in the Encyclopaedia

General Conversions

Lists all General Conversions in the Encyclopaedia

General Theory of Relativity

An extension of the special theory of relativity to include the concept of gravity.

General Weblinks

Lists all General Weblinks in the Encyclopaedia

Generator Rule

Also known as the Fleming′s Right Hand Rule this is a way of determining the direction of the induced emf of a conductor moving in a magnetic field.

Genetic Algorithm

A type of optimization algorithm that uses Darwinian principles to evolve a solution to a mathematical model based on survival of the fittest.

Genetic Engineering

A man-made method of altering the genes to change the characteristics of an organism.

Geocentric Model

A model of the Universe with the Earth at its center.

Geocorona

The outermost layer of the Earth′s neutral atmosphere.

Geodesic

The arc on a surface of shortest length joining two given points.

Geodesy

The study of the shape of the Earth, e.g. its deviations from an exact sphere.

Geodetic Coordinates

A system of geographic position referencing. Angular measurements of latitude and longitude are projected onto a well-defined reference ellipsoid that approximates the earth′s irregular shape.

Geological Timescale

The ages of the history of planet earth from the Pleistocene to the Precambrian era.

Geology

Lists all the Geology topics

Geology Weblinks

Lists all Geology Weblinks in the Encyclopaedia

Geomagnetic Field

The magnetic field observed in and around the Earth.

Geometric Mean

A statistic calculated by multiplying n data values together and taking the n-th root of the result.

Geometric Optics

That branch of optics dealing with the tracing of ray paths through optical systems.

Geometric Scattering

Acoustic scattering in which the wavelength of the sound used is much smaller than the size of object causing the scattering.

Geometrized Units

A system of units whereby certain fundamental constants are set to unity.

Geometry

The branch of mathematics that deals with the nature of space and the size, shape, and other properties of figures as well as the transformations that preserve these properties.

Geostationary

A satellite orbit traveling from west to east at speeds that allow it to remain fixed over a given place on the earth′s equator at approximately 22,300 miles in altitude. A geostationary satellite makes one revolution in 24 hours, synchronous with the earth′s rotation.

Geotropism

Movement of a plant in response to gravity.

German Silver

This describes a number of alloys that contain copper (25 to 50%), zinc (10 to 35%) and nickel (5 to 35%) within the limits given.

Germanium

A silvery white brittle metalloid member of the carbon group of elements. Its physical properties being similar to those of silicon.

Germination

The growth of a new plant from a seed.

Gestation Period

The length of gestation, the time from conception to birth. For humans this is 266 days.