Copyright © Philip M. Parker, INSEAD. Terms of Use.

ROOT MEAN SQUARE

Specialty Definition: ROOT MEAN SQUARE

DomainDefinition

Post & Telecom

The square root of the mean of the square of the signal taken during one full cycle. Source: European Union. (references)

Source: compiled by the editor from various references; see credits.

Top     

Specialty Definition: Root mean square

(From Wikipedia, the free Encyclopedia)

The root mean square or rms is a statistical measure of the magnitude of a varying quantity. It can be calculated for a series of discrete values or for a continuously varying function. The name comes from the fact that it is the square root of the mean of the squares of the values.

The rms for a collection of N values {x1, x2, ... , xN} is:

and the corresponding formula for a continuous function f(t) defined over the interval T1 ≤ t ≤ T2 is:

Uses

The rms value of a function is often used in physics. For example, we may wish to calculate the power P dissipated by an electrical conductor of resistance R. It is easy to do the calculation when a constant current I flows through the conductor. It is simply,

(1)

But what if the current is a varying function I(t)? This is where the rms value comes in. It may be shown that the rms value of I(t) can be substituted for the constant current I in the above equation to give the mean power dissipation, thus:

(2)

In the common case when I(t) is a sinusoidal current, as is approximately true for mains power, the rms value is easy to calculate from equation (2) above. The result is:

where Ip is the amplitude.

The rms value can be calculated using equation (2) for any waveform, for example an audio or radio signal. This allows us to calculate the mean power delivered into a specified load.

It is important to note that rms is a mean value and not an instantaneous measurement. Therefore expressions such as "peak rms power", sometimes used in advertisements for audio amplifiers, are misleading. See also PMPO.

Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Root mean square."

Top     

Crosswords: ROOT MEAN SQUARE

Specialty definitions using "ROOT MEAN SQUARE": Airborne Snow Water Equivalent Measurement Theory. (references)

Top     

Expression: ROOT MEAN SQUARE

Expression using "ROOT MEAN SQUARE": root mean square value. Additional references.

Source: compiled by the editor from various references; see credits.

Top     

Frequency of Internet Keywords: ROOT MEAN SQUARE

The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com.
 
ExpressionFrequency
per Day

root mean square

48
Source: compiled by the editor from various references; see credits.

Top     

Modern Translation: ROOT MEAN SQUARE

Language Translations for "ROOT MEAN SQUARE"; alternative meanings/domain in parentheses.

Danish

  

r.m.s.-vaerdi (quadratic mean), kvadratisk middel (quadratic mean), effektivvaerdi (quadratic mean). (various references)

   

Dutch

  

root mean square (quadratic mean), RMS (quadratic mean), r.m.s. (quadratic mean), standaardafwijking (quadratic mean, repeatable dosing error, standard deviation), effectieve waarde (quadratic mean). (various references)

   

Finnish

  

neliöllinen keskiarvo (quadratic mean). (various references)

   

French

  

valeur quadratique moyenne, valeur efficace, moyenne quadratique. (various references)

   

German

  

quadratischer Mittelwert (quadratic mean), Effektivwert (quadratic mean). (various references)

   

Greek 

  

ενεργός τιμή (quadratic mean). (various references)

   

Italian

  

scarto quadratico medio (mean square deviation, quadratic mean, variance). (various references)

   

Pig Latin

  

ootray eanmay aresquay

   

Portuguese

  

valor quadrático médio (quadratic mean), valor eficaz (quadratic mean). (various references)

   

Spanish

  

raíz cuadrada de la media de los cuadrados (quadratic mean), valor r.m.s. (quadratic mean), valor eficaz (quadratic mean), valor cuadrático medio (quadratic mean), media cuadrática (quadratic mean). (various references)

   

Swedish

  

effektivvärde (root mean square value). (various references)

Source: compiled by the editor from various translation references.

Top     

Anagrams: ROOT MEAN SQUARE

Scrabble® Enable2K-Verified Anagrams

Words within the letters "a-a-e-e-m-n-o-o-q-r-r-s-t-u"

-3 letters: enumerators.

-4 letters: aeronomers, astronomer, enumerator, numerators.

-5 letters: aeronauts, aeronomer, anterooms, aquatones, armatures, emanators, erroneous, monoester, neuromata, numerates, numerator, orometers, quarterns, ratooners, rearmouse, remarques, renatures, requestor, resonator, rousement, saunterer.

Source: compiled by the editor from various references; see credits.

SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro.

Top     



INDEX

1. Crosswords
2. Expressions
3. Expressions: Internet
4. Translations: Modern 		5. Anagrams
6. Bibliography


  

Copyright © Philip M. Parker, INSEAD. Terms of Use.