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
Heat and Mass Transfer Heat is transferred by all three modes of transfer, viz. conduction, convection and radiation in Steam condenser Refrigerator condenser coils Boiler Electric heater Steam condenser Refrigerator condenser coils Boiler Electric heater ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Planck’s law holds good for all coloured bodies All of these polished bodies black bodies all coloured bodies All of these polished bodies black bodies ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Cork is a good insulator because it has Atoms colliding frequency Porous body Free electrons Low density Atoms colliding frequency Porous body Free electrons Low density ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The amount of heat flow through a body by conduction is Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body Dependent upon the material of the body All of these Directly proportional to the surface area of the body Directly proportional to the temperature difference on the two faces of the body Dependent upon the material of the body All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A heat exchanger with heat transfer surface area A and overall heat transfer coefficient U handles two fluids of heat capacities Cmax and Cmin. The number of transfer units (NTU) used in the analysis of heat exchanger is specified as U/Cmin Cmin/U U.Cmin U/A.Cmin U/Cmin Cmin/U U.Cmin U/A.Cmin ANSWER DOWNLOAD EXAMIANS APP