Heat and Mass Transfer According to Newton's law of cooling, the heat transfer from a hot body to a cold body is Directly proportional to the surface area Either (A) or (B) Both (A) and (B) Directly proportional to the difference of temperatures between the two bodies Directly proportional to the surface area Either (A) or (B) Both (A) and (B) Directly proportional to the difference of temperatures between the two bodies ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal diffusivity of a substance is given by (where h = Thermal diffusivity, ρ = Density of substance, S = Specific heat, and k = Thermal conductivity) h = kρ/S h = S/ρk h = k/ ρS h = ρS/k h = kρ/S h = S/ρk h = k/ ρS h = ρS/k ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The value of the wavelength for maximum emissive power is given by Fourier's law Planck's law Wien’s law Stefan's law Fourier's law Planck's law Wien’s law Stefan's law ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is K cal m/hr m² °C K calm/hr °C K cal/hr m² °C K cal/kg m² °C K cal m/hr m² °C K calm/hr °C K cal/hr m² °C K cal/kg m² °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 60°C 20°C 66.7°C 40°C 60°C 20°C 66.7°C 40°C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Fouling factor is used In heat exchanger design as a safety factor In case of Newtonian fluids When a liquid exchanges heat with a gas None of these In heat exchanger design as a safety factor In case of Newtonian fluids When a liquid exchanges heat with a gas None of these ANSWER DOWNLOAD EXAMIANS APP