scale

In music, a progression of single notes upwards or downwards in ‘steps’ (scale originally meant ‘ladder’). For example, the most common scale is that of C major, which can be found by playing all the white notes on the keyboard from any C to the next C above or below. A scale is defined by its starting note and may be major or minor depending on its arrangement of tones and semitones. A chromatic scale is made up entirely of semitones. It includes all the notes (black and white) on the keyboard and has no key because there is no fixed starting point.

A whole-tone scale is a six-note scale and is also indeterminate in key. This scale originated in the South Sea Islands and was used extensively by Claude Debussy. A diatonic scale has seven notes, a pentatonic scale has five.

scale

In chemistry, calcium carbonate precipitates that form on the inside of a kettle or boiler as a result of boiling hard water (water containing concentrations of soluble calcium and magnesium salts). The salts present in hard water also precipitate out by reacting with soap molecules.

Scale may cause damage to water pipes and appliances such as washing machines and water boilers. The build-up of scale causes blockage of pipes, and electrical appliances have to use more electrical energy to operate efficiently.

scale

Numerical relationship, expressed as a ratio, between the actual size of an object and the size of an image that represents it on a map, plan, or diagram.

If an object has been enlarged, the amount of increase (scale factor) can be found by dividing a side of the enlarged object by the corresponding side of the original shape. A scale factor of less than one gives a decrease in size. An object is scaled by multiplying it by the scale factor; for example, a model railway may require a scale of 1 in a 100, so all measurements must be multiplied by 1/100 (0.01).