القدرة الكهربائية الردفعلية;الردية
"Reactive Power", for a linear two-terminal element or two-terminal circuit, under sinusoidal conditions, is the quantity equal to the product of the apparent power $S$ and the sine of the displacement angle $\psi$. The absolute value of the reactive power is equal to the non-active power. The ISO (and SI) unit for reactive power is the voltampere. The special name $\textit{var}$ and symbol $\textit{var}$ are given in IEC 60027 1.
Applicable units are those of quantitykind:ReactivePower
http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=31891
http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=131-11-44
https://cdd.iec.ch/cdd/iec61987/iec61987.nsf/ListsOfUnitsAllVersions/0112-2---62720%23UAD155
$Q = lm \underline{S}$, where $\underline{S}$ is complex power. Alternatively expressed as: $Q = S \cdot \sin \psi$, where $\psi$ is the displacement angle.