Elastance

Electrical elastance is the inverse of capacitance. The SI unit is the reciprocal farad. Although the term daraf (farad spelled backwards) is sometimes used, this is not approved by SI. Electrical inductor-capacitor-resistor circuits follow differential equations that can be interpreted as representing mass-spring-damper systems. If voltage is taken to be force and current velocity, elastance corresponds to the elastic constant of a spring.