ENGLISH
REFERENCE

RMS

n. uncountable
C2 Proficiency rms

n. Stands for Root Mean Square. A way to calculate the average value of a set of numbers that change over time, like an electrical signal or sound wave. It helps you understand the true power or strength of the signal.

n. Abbreviation for Root Mean Square. A statistical measure of the magnitude of a varying quantity, calculated as the square root of the arithmetic mean of the squares of the values. It is the standard method for expressing the effective value of alternating current or audio signals.


SIMPLE

The speakers have an RMS power rating of 50 watts.

CONTEXTUAL

Engineers use the RMS value to determine the effective voltage of an AC power supply, as it represents the equivalent DC power.

COMPLEX

When comparing audio amplifiers, the RMS power output provides a more accurate representation of sustained performance than the peak power rating, which only measures short bursts of energy.

Usage

Often used as a modifier before another noun (e.g., 'RMS voltage', 'RMS power').

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