Sa

Sabin

The unit of measure of sound absorption in the inch-pound system. A measure of the sound absorption of a surface. One sabin is the equivalent to one square foot of a perfectly absorptive surface.

Sabine Formula

The Sabine formula is derived from the Norris-Eyring formula for small absorption coefficients.

Sabine, Wallace Clement

The Harvard professor honoured as the father of architectural acoustics for his investigations into concert hall sound at the turn of the century.

Saccade

The normal, but largely unnoticed rapid darting of the eyes from one fixed point to another.

SAE Steel

Steel manufactured under the specifications by the Society of Automotive Engineers.

Safety Pin

A simple pin that clips shut most commonly used to fasten two pieces of fabric.

Sag

Deflection due to gravity acting on a cantilevered or otherwise supported object.

Sagnac Effect

First discovered in 1913 by Georges Sagnac, it involves sending two beams of light in opposite directions around a closed path and then using a detector to examine the beams when they arrive back at the starting point.

Sal Ammoniac

Old name for Ammonium Chloride.

Salmanazar

The name of a wine bottle equivalent to the volume of 12 standard bottles or 9 litres.

Salt

Sodium chloride.

Salt of Tartar

An old fashioned name for Potassium Carbonate.

Salt of Wormwood

Old fashioned name for Potassium Carbonate.

Saltpetre

Old fashioned name for Potassium Nitrate or Sodium Nitrate.

Salts

Ionic compounds that can be formed by replacing one or more of the hydrogen ions of an acid with another positive ion.

Samarium

A relatively stable element in dry air but oxidises on contact with moisture.

Sample

A set of observations, usually considered to have been taken from a much larger population.

Sampling Frequency

The frequency or rate at which an analog signal is sampled or converted into digital data.

Sand

A term generally given to rock with a grain size between 1/16mm and 2mm.

Sandblasting

A process of blowing sand by compressed air with considerable force through a hose against an object.

Sandpaper

An abrasive paper used to smooth the rough edges of freshly sawn wood.

Sapid

To have a decided, yet pleasant taste.

Saponaceous

To be soapy, slippery, sometimes foaming.

Satellite

An object in an orbit around a planet.

Saturated Liquid

Purely liquid, but at the saturation temperature any additional heat will cause some vapourisation.

Saturation Velocity

Maximum velocity which can be obtained in a specific semiconductor.

Saturn

The sixth planet from the sun in our solar system.

Saw

A tool with a blade or disc with teeth along the edge used to cut metal, wood, plastic and many other materials.