However, elastance is used in theoretical work in network analysis and has some niche applications, particularly at microwave frequencies.
It is also the name of the generalized quantity in bond-graph analysis and other schemes that analyze systems across multiple domains.
where L, R, S, and Z are the network loop matrices of inductance, resistance, elastance, and impedance, respectively, and s is complex frequency.
The use of elastance here is primarily for mathematical convenience, similar to how mathematicians use radians rather than more common units for angles.
In this field, varactor diodes are used as voltage-variable capacitors in devices such as frequency multipliers, parametric amplifiers, and variable filters.
These diodes store charge in their junction when reverse biased, which generates the capacitor effect.
[7] Heaviside coined many of the terms used in circuit analysis today, such as impedance, inductance, admittance, and conductance.
Heaviside's nomenclature was designed to emphasize the connection between corresponding quantities in fields and circuits.
Heaviside denied the idea of physical charge flow and accumulation on capacitor plates, replacing it with the concept of the divergence of the displacement field at the plates, which was numerically equal to the charge collected in the flow view.
[14] Today, however, the reciprocal terms capacitance and permittivity are almost universally preferred by electrical engineers.
[15] Heaviside carefully crafted his terminology to be unique to electromagnetism, specifically avoiding overlaps with mechanics.
Ironically, many of his terms were later borrowed back into mechanics and other domains to describe analogous properties.
However, elastance is widely used for the analogous property in the domain of fluid dynamics, particularly in fields such as biomedicine and physiology.
The second, and more significant, reason is to analyze systems containing both mechanical and electrical components as a unified whole.
This approach is especially beneficial in fields like mechatronics and robotics, where integration of mechanical and electrical elements is common.
The term "electromotive force" used for the voltage of an electric power source reflects this analogy.
The term elastance is used in the formal analysis of systems involving multiple energy domains, such as in bond graphs.