Heat and Mass Transfer Upto the critical radius of insulation, Added insulation will increase heat loss Convective heat loss will be less than conductive heat loss Added insulation will decrease heat loss Heat flux will decrease Added insulation will increase heat loss Convective heat loss will be less than conductive heat loss Added insulation will decrease heat loss Heat flux will decrease ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A cube at high temperature is immersed in a constant temperature bath. It loses heat from its top, bottom and side surfaces with heat transfer coefficients of h₁, h₂ and h₃ respectively. The average heat transfer coefficient for the cube is 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ None of these (h₁.h₂.h₃)1/3 1/h₁ + 1/h₂ + 1/h₃ h₁ + h₂ + h₃ None of these (h₁.h₂.h₃)1/3 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Heat flows from one body to other when they have Different atomic structure Different temperatures Different specific heat Different heat contents Different atomic structure Different temperatures Different specific heat Different heat contents ANSWER DOWNLOAD EXAMIANS APP
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 = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 8πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Reynolds number (RN) is given by (where h = Film coefficient, l = Linear dimension, V = Velocity of fluid, k = Thermal conductivity, t = Temperature, ρ = Density of fluid, cp = Specific heat at constant pressure, and μ = Coefficient of absolute viscosity) RN = V²/t.cp RN = μ cp/k RN = hl/k RN = ρ V l /μ RN = V²/t.cp RN = μ cp/k RN = hl/k RN = ρ V l /μ ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be white when (Where a = absorptivity, p = reflectivity, x = transmissivity) P = 0, x = 0 and a = 1 P=1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 P=1, T = 0 and a = 0 P = 0, x = 1 and a = 0 X = 0, a + p = 1 ANSWER DOWNLOAD EXAMIANS APP