Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The radiation emitted by a black body is known as Black radiation Total radiation Full radiation All of these Black radiation Total radiation Full radiation All of these ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The automobile radiator is a heat exchanger of Regenerator type Parallel flow type Cross flow type Counter flow type Regenerator type Parallel flow type Cross flow type Counter flow type 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/A.Cmin Cmin/U U/Cmin U.Cmin U/A.Cmin Cmin/U U/Cmin U.Cmin ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Film coefficient is defined as the ratio of Thermal conductivity to the equivalent thickness of the film of fluid Thickness of film of fluid to the temperature drop through the films of fluids Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the thermal conductivity Thermal conductivity to the equivalent thickness of the film of fluid Thickness of film of fluid to the temperature drop through the films of fluids Temperature drop through the films of fluids to the thickness of film of fluids Thickness of film of fluid to the thermal conductivity 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 = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) tm = loge (Δt1/Δt2)/ (Δt1 - Δt2) tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2) tm = loge (Δt1 - Δt2)/ Δt1/Δt2 tm = (Δt1 - Δt2)/ loge (Δt1/Δt2) ANSWER DOWNLOAD EXAMIANS APP