Dielectric strength of a material depends on

moisture content
temperature
thickness
all of the above

The correct answer is: D. all of the above

Dielectric strength is the maximum electric field strength that a material can withstand without breaking down and allowing current to flow. It is a measure of the material’s resistance to electrical breakdown.

The dielectric strength of a material depends on a number of factors, including the following:

  • Moisture content: The presence of moisture in a material can weaken its dielectric strength. This is because water molecules can act as a path for current flow, leading to breakdown.
  • Temperature: The dielectric strength of a material decreases with increasing temperature. This is because the molecules in a material move more quickly at higher temperatures, making it easier for them to break down and allow current to flow.
  • Thickness: The dielectric strength of a material is inversely proportional to its thickness. This is because the electric field strength is higher at the surface of a material than it is at the center. Therefore, a thicker material will have a lower dielectric strength than a thinner material.

In addition to these factors, the dielectric strength of a material can also be affected by its composition, structure, and surface finish.