Related Experiment Video
Updated: Jun 23, 2026

The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Abstract:
We examine the energy exchanged between an electromagnetic pulse and a linear dielectric medium in which it propagates. While group velocity indicates the presence of field energy (the locus of which can move with arbitrary speed), the velocity of energy transport maintains strict luminality. This indicates that the medium treats the leading and trailing portions of the pulse differently. The principle of causality requires the medium to respond to the instantaneous spectrum, the spectrum of the pulse truncated at each new instant as a given locale in the medium experiences the pulse.
Related Concept Videos
Electrical Transport
Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
Carrier Transport
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Gauss's Law in Dielectrics
Dielectric Polarization in a Capacitor
The Electrical Double Layer

