Q1: Thickness of thermal boundary layer is more compared to that of hydrodynamic boundary layer, when the value of Prandtl number is

ANS:B - < 1

The thickness of the thermal boundary layer is more compared to that of the hydrodynamic boundary layer when the value of the Prandtl number (Pr) is: b) < 1 The Prandtl number (Pr) is the ratio of momentum diffusivity to thermal diffusivity in a fluid. When the Prandtl number is less than 1, it indicates that momentum diffuses faster than heat. In such cases, the thermal boundary layer tends to be thicker compared to the hydrodynamic boundary layer. This is because the momentum diffuses rapidly through the fluid, causing the fluid velocity to change more quickly than the temperature, resulting in a thinner hydrodynamic boundary layer and a thicker thermal boundary layer.