Effective Mass: The mass of a body which is being acted upon by the buoyant forces of air. The effective mass of a weight is its true mass minus the buoyant force of air displaced by the weight.

Effective Value (RMS): The alternating current value that will produce the same amount of heat in a resistance as the corresponding direct current value.

Efficiency: The ration of useful output energy, usually expressed as a percentage.

Effluent: Liquid that has passed through a processing operation.

Elastic Element: The material of which the transducer is constructed, generally selected for its good elastic properties.

Electrical Relay : Employs a solenoid to provide mechanical action to move a varying number of electrical contacts back and forth or on and off.

Electronic Switch: An electric circuit designed to cause a start and stop action or a switching action.

Electrostatic Field: The region surrounding an electric charge in which another charge experiences a force.

Element: A quality of product, material, or service forming a cohesive entity on which a measurement or observation may be made.

Empirical: Based on actual measurement, observation, or experience without regard to science and theory.

Endoergic Reaction: A reaction which absorbs energy.

ERG: A CGS unit of work or energy.

Error (of measurement): The result of a measurement minus the true value of the measurnand.

Exoergic Reaction: The reaction which liberates energy.

Explosion Proof Motor(XPRF): A totally enclosed motor that will withstand an explosion of a specific vapor or gas within its housing, or will prevent sparks or flashes generated within its housing from igniting surrounding vapor or gas.

Factory Calibration: The tuning or altering of a control device by the manufacture to bring it into specification.

Fahrenheit Scale: A temperature scale that defines the freezing point of water as 32 degrees and the boiling point of water a 212 degrees.

Fixed Point: The point where all heat energy applies or removed is used to change the state of a substance.

Flux: (1) A material used to promote fusion or joining of metals in soldering, welding, or smelting. (2) A general term used to designate collectively all the electric or magnetic lines of force in a region.

Force Measurement Device: Any device which a quantitative determination of an applied force can be made.

Force: A push or pull which produces or prevents motion or has a tendency to do so.

Forced Vibration: The motion caused by some mechanical excitation.

Free Vibration: Vibration that occurs without forcing.

Frequency Meter: An instrument for measuring the frequency of an AC signal.

Frequency: The number of recurrences of a periodic phenomenon.

Full Scale Output (FSO): The output at rated capacity minus the output at zero applied force.

Function Tests: Function test often duplicates unit test activities sincefunction testers do not assume that unit test is adequately done.

Fundamental Method of Measurement: The method of measurement in which the value of a measurand is obtained by measurement of the appropriate base quantities.

Fundamental Mode of Vibration: The lowest natural frequency.

Gage Block: A block of alloy steel with two gaging surfaces.

Gage: A measuring instrument for measuring and indicating a quantity.

Gain: Ratio of output voltage, current, or power to input voltage current or power.

Galvanometer: Meter for detecting or comparing or measuring small electric currents.

Gamma Ray: Electromagnetic radiation emitted during radioactive decay and having an extremely short wavelength.

Gas: The state of matter that has no definite shape of volume.

Gauge Factor: The sensitivity of the strain gauge.

Gauge Pressure (psig): A measure of the force per area exerted by a fluid using atmospheric pressure as a zero reference.

Gauss: Unit of magnetic induction.

Go and No Go Gages: Gages that do not measure actual size but merely determine whether parts are within specified limits.

Grain: A measure of mass in the English gravitational system equal to 1/7000th pound.

Gram: A metric unit of weight equal to one thousandth of a kilogram.

Gram Atomic Weight: The quantity of an element whose weight in grams is numerically equal to the atomic weight of the element.

Gram Molecular Weight (Gram-Mole): The relative molecular weight of a compound, expressed in grams.

Graticule: A network of fine lines, dots, cross hairs, or wires in the focal plane of the eyepiece of an optical instrument.

Gravitational Acceleration: The acceleration due to the force of gravity.

Guardband: Also called a frequency guard band, a narrow frequency band between adjacent channels in multiplexing that is kept unused to prevent the channels from overlapping and causing crosstalk among modulated signals.

Half Life: The length of time during which half a given number of atoms of a radioactive element will disintegrate.

Half Thickness: The thickness of absorbing material necessary to reduce the intensity of radiation by one-half.

HCI: Hydrochloric acid.

Heat of Fusion: The amount of heat needed to melt a unit mass or weight of a substance at its normal melting point.

Heat of Vaporization: Heat required to vaporize a unit mass or weigh of a liquid at its normal boiling point.

Hertz: The unit of frequency.

Hold Point: Point defined in an appropriate document, beyond which an activity must not proceed without the approval of a designated organization or authority.

Hunting: The tendency of a mechanical system to oscillate about a normal condition, or about the point of alignment.

Hydrometer : A measuring instrument for determining the specific gravity of a liquid or solid.

Hydraulics: Study of liquids in motion.

Hydrostatics: Study of liquids at rest.

Hygrometer: Measuring instrument for measuring the relative humidity of the atmosphere.

Hysteresis: The property of a measuring instrument where its response to a given stimulus depends of the sequence of preceding stimuli.

Impedance: The opposition in an electric circuit to the flow of an alternating current.

Index of Refraction: The ratio of the speed of light in a vacuum to its speed in a given substance.

Inductive Load: Electrical devices made of wound or coiled wire.

Influence Quantity: Any effect that may influence the uncertainty associated with a measurement value.

Inertia: The tendency of a body to maintain is state of rest or uniform motion unless acted upon by an external force.

Infinite: Subject to no limitation or external determination, extending indefinitely.

Initialization: Setting a system to a known state.

Inspection: The process of measuring, examining, testing, gauging, or otherwise comparing the unit with the applicable instruments.

Inspection by Attributes: This is inspection whereby either the unit of product is classified as conforming or nonconforming, or the number of nonconformities in the product is counted, with respect to a given requirement or set of requirements.

Instability: An undesired change over a period of time, which change is unrelated to input, operating conditions, or load.

Interferometer: Any measuring instrument that uses interference patterns to make accurate measurements of waves.

Interpolation: Calculation of the value of a function between the values already known.

ISO: International Organization for Standardization.

Inversion: The condition that exists when both axes of an image are reversed.

Inverter: Any mechanical or electrical device for converting direct current into alternating current.