In what units is thermal resistivity typically expressed?

Thermal resistivity is a measure of a material's ability to resist the flow of heat. It is typically expressed in units that reflect the relationship between temperature difference, heat transfer, and material dimensions.

The correct answer, which expresses thermal resistivity, is represented as C-cm/watt. This unit indicates how much heat flow (in watts) is required to maintain a temperature gradient given a specific thickness of material (in centimeters). Essentially, it describes how resistive the material is to thermal conduction for specific dimensions and temperature differences.

The other options do not align with the definition of thermal resistivity. Joules per watt pertains to energy transfer rate relative to power and is not a direct measurement of resistivity. Watts per meter relates more to thermal conductivity rather than resistivity, as it describes how effectively a material conducts heat rather than its resistance to heat flow. Degrees Celsius is a temperature measurement and does not convey information about thermal resistance.