Q1: Which of the following pair is correctly matched?

ANS:D - all 'a', 'b' & 'c' are correctly matched.

When all options are stated to be correctly matched, it implies that each pair matches the corresponding term with its correct characteristic. Let's break down each pairing: a) Heat transfer: Thermal diffusivity - This pair is correctly matched. Thermal diffusivity is a property of a material that describes how quickly it can conduct heat relative to its ability to store thermal energy. It is defined as the ratio of thermal conductivity to the product of density and specific heat capacity. Therefore, in the context of heat transfer, thermal diffusivity is indeed the relevant characteristic. b) Mass transfer: Diffusion coefficient - This pair is correctly matched. In mass transfer, the rate at which a substance diffuses through a medium is characterized by the diffusion coefficient. This coefficient represents the proportionality between the flux of the substance and the concentration gradient. Thus, it accurately represents the process of mass transfer through diffusion. c) Momentum transfer: Kinematic viscosity - This pair is correctly matched. Kinematic viscosity is a property of a fluid that quantifies its resistance to flow under the influence of an external force, such as gravity or pressure. It is defined as the ratio of dynamic viscosity to density. In the context of momentum transfer, kinematic viscosity plays a crucial role in determining how easily momentum is transferred within the fluid. Therefore, when all options are stated to be correctly matched, it indicates that each pair accurately associates the term with its relevant characteristic or property in the respective field of study.