J/mm
C/m2
kV/mm
N/mm
Answer is Wrong!
Answer is Right!
The correct answer is C. kV/mm.
Dielectric strength is the maximum electric field strength that a material can withstand without breaking down and becoming conductive. It is usually expressed in kilovolts per millimeter (kV/mm).
Option A, J/mm, is the unit of energy per unit volume. It is not used to express dielectric strength.
Option B, C/m2, is the unit of charge per unit area. It is not used to express dielectric strength.
Option D, N/mm, is the unit of force per unit length. It is not used to express dielectric strength.