Heat Transfer The heat transfer by radiation from a mild steel surface is to be reduced by reducing the emissivity of the surface. This can be best achieved by Painting the surface white (with aluminium paint) Roughening the surface Painting the surface black Giving the surface a mirror finish Painting the surface white (with aluminium paint) Roughening the surface Painting the surface black Giving the surface a mirror finish ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A BTU/hr.ft.2 °F is equal to None of these 4.88 kcal/hr. m.2°C 1 kcal/hr. m².°K 1 kcal/hr. m²°C None of these 4.88 kcal/hr. m.2°C 1 kcal/hr. m².°K 1 kcal/hr. m²°C ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer At constant temperature, the thermal conductivities of gases __________ with rise in pressure. Remain unchanged Decrease May increase or decrease; depends on the pressure Increase Remain unchanged Decrease May increase or decrease; depends on the pressure Increase ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Maximum water velocity in tubes of a 1-2 shell and tube heat exchanger may be around __________ metres/second. 10 20 30 1 10 20 30 1 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Prandtl and Reynold's analogies are identical for Prandtl number value of 5 0.5 1 5 0.5 1 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer In case of heat transfer by conduction in a hollow cylinder, __________ mean area is used to calculate the heat transfer rate. Logarithmic Arithmetic Geometric Either A, B or C Logarithmic Arithmetic Geometric Either A, B or C ANSWER DOWNLOAD EXAMIANS APP