Q1: Thermal conductivity of a material does not depend upon its

ANS:D - all 'a', 'b' & 'c'

1. Mass: Thermal conductivity is an intensive property, meaning it is independent of the amount or mass of the material. Whether you have a small sample or a large sample of the same material, the thermal conductivity remains the same. This is because thermal conductivity is a property of the material itself and is not affected by the quantity of material present.
2. Volume: Similar to mass, thermal conductivity is not influenced by the volume of the material. Even if you have different volumes of the same material, the thermal conductivity remains constant. The reason for this is that thermal conductivity is related to the material's intrinsic properties and how its atoms or molecules interact with heat energy, which is independent of the material's volume.
3. Surface Area: The surface area of a material also does not affect its thermal conductivity. Thermal conductivity is determined by the material's internal structure and how effectively it can transfer heat through conduction. The surface area only affects how heat is transferred between the material and its surroundings, but it does not impact the material's inherent ability to conduct heat internally.

In summary, thermal conductivity is solely dependent on the material's intrinsic properties, such as its atomic or molecular structure, and is unaffected by its mass, volume, or surface area. This property makes it useful for comparing different materials' ability to conduct heat under the same conditions, regardless of their size or shape.