Heat and Mass Transfer A grey body is one whose absorptivity Does not vary with temperature and. wavelength of the incident ray Varies with wavelength of the incident ray Varies with temperature Is equal to its emissivity Does not vary with temperature and. wavelength of the incident ray Varies with wavelength of the incident ray Varies with temperature Is equal to its emissivity ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The critical radius is the insulation radius at which the resistance to heat flow is Minimum None of these Zero Maximum Minimum None of these Zero Maximum ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of the energy absorbed by the body to total energy falling on it is called Absorptivity Absorptive power Emissivity Emissive power Absorptivity Absorptive power Emissivity Emissive power ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer by conduction through a thick sphere is given by 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) Q = 2πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 6πkr1 r2 (T1 - T2)/ (r2 - r1) Q = 4πkr1 r2 (T1 - T2)/ (r2 - r1) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer In heat transfer, conductance equals conductivity (kcal/hr/sq.m/°C/cm) divided by Sq. m (area) Hr (time) °C (temperature) K.cal (heat) Sq. m (area) Hr (time) °C (temperature) K.cal (heat) ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For the minimum heat transfer, One could place either insulation on either side The better insulation must be put outside The better insulation must be put inside One should take into account the steam temperature before deciding as to which insulation is put where One could place either insulation on either side The better insulation must be put outside The better insulation must be put inside One should take into account the steam temperature before deciding as to which insulation is put where ANSWER DOWNLOAD EXAMIANS APP