effektforhold

Effektforhold is a term used in Scandinavian engineering and physics to describe the relationship between two effects or powers within a system. It refers to how much of an input or reference power is observed as a particular output or secondary effect. In practice, effektforhold is usually expressed as a ratio or a dimensionless number.

Mathematically, effektforhold is the quotient of two powers, such as P_out / P_in, or more generally the ratio between two effects with the same or compatible dimensions. When both quantities are powers measured with the same units, effektforhold is dimensionless and can be presented as a decimal or as a percentage. A value less than one indicates partial conversion or transfer, while a value greater than one would indicate amplification, if physically possible under the given conditions.

The term is used across several domains. In mechanical systems, it often describes how much input power a machine delivers as useful output power (for example, a motor with 1000 W input and 800 W output has an effektforhold of 0.8, or 80%). In electrical and signal processing, it can denote the power gain from input to output. In hydraulics or acoustics, it may compare delivered versus available power or energy in a stage of a system. The concept is related to efficiency and gain, but effektforhold emphasizes the ratio of effects rather than the proportion of input energy converted.

Because effektforhold can be defined in different ways, it is important to specify which quantities are being compared and over what conditions. See also efficiency, gain, and power ratio.