Dielectric strength is usually expressed in terms of what measurement?

Dielectric strength is a critical parameter in electrical engineering, particularly in understanding how insulating materials behave under high voltage conditions. It is defined as the maximum electric field that a material can withstand without experiencing breakdown, which is when the material begins to conduct electricity. This breakdown can lead to electrical failure or short circuits.

Dielectric strength is expressed in volts per unit thickness of the material, typically in volts per millimeter (V/mm) or kilovolts per millimeter (kV/mm). This measurement reflects the ability of the material to resist electrical breakdown and is essential in the selection of insulating materials for various applications in electrical systems.

Understanding dielectric strength is crucial for ensuring safety and reliability in electrical designs, as it helps in selecting materials that can prevent unwanted current flow, especially in high-voltage environments. Therefore, the correct answer is volts, as it directly relates to the measure of electric field strength that an insulating material can endure before failing.