Convection

Radiation

Conduction

Both convection and conduction

**According to Stefan Boltzmann law, ideal radiators emit radiant energy at a rate proportional to****The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is****Metals are good conductors of heat because****A heat exchanger with heat transfer surface area A and overall heat transfer coefficient U handles two…****Thermal conductivity of a material may be defined as the****The unit of overall coefficient of heat transfer is****The unit of Stefan Boltzmann constant is****In case of liquids and gases, the heat transfer takes place according to****Thermal diffusivity of a substance is****The heat is transferred by conduction, convection and radiation in****Absorptivity of a body will be equal to its emissivity****The ratio of the thickness of thermal boundary layer to the thickness of hydrodynamic boundary layer…****Fourier's law of heat conduction gives the heat flow for****Reynolds number is the ratio of****The ratio of surface convection resistance to the internal conduction resistance is known as****The product of Reynolds number and Prandtl number is known as****The process of heat transfer from one particle of the fluid to another by the actual movement of the…****Log mean temperature difference in case of counter flow compared to parallel flow will be****Thermal conductivity of water ________ with rise in temperature.****Unit of thermal conductivity in S.I. units is****Stefan Boltzmann law is applicable for heat transfer by****According to Stefan's law, the total radiation from a black body per second per unit area is proportional…****Total emissivity of polished silver compared to black body is****If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ,…****The critical radius is the insulation radius at which the resistance to heat flow is****A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities.…****Wiens law states that the wave length corresponding to ________ is proportional to the absolute temperature.****Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly…****In a heat exchanger with one fluid evaporating or condensing, the surface area required is least in****Emissivity of a white polished body in comparison to a black body is**