Heat and Mass Transfer Unit of thermal conductivity in M.K.S. units is K cal/kg m² °C K calm/hr °C K cal m/hr m² °C K cal/hr m² °C K cal/kg m² °C K calm/hr °C K cal m/hr m² °C K cal/hr m² °C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer from a hot body to a cold body is directly proportional to the surface area and difference of temperatures between the two bodies. This statement is called First law of thermodynamics Stefan's law Newton's law of cooling Newton's law of heating First law of thermodynamics Stefan's law Newton's law of cooling Newton's law of heating ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Atoms colliding frequency Free electrons Low density Porous body Atoms colliding frequency Free electrons Low density Porous body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power depends on temperature Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Emissive power depends on temperature ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is the case of heat transfer by radiation? Blast furnace Heating of building Cooling of parts in furnace Heat received by a person from fireplace Blast furnace Heating of building Cooling of parts in furnace Heat received by a person from fireplace ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP