Heat Transfer One kilogram of water at 0°C is changed to superheated steam of one atm pressure and 300° C. The major heat consumption in the process will be to Evaporate the water Heat the water from 0°C to 100°C Data insufficient, can To superheat the steam Evaporate the water Heat the water from 0°C to 100°C Data insufficient, can To superheat the steam ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer For a perfectly transparent surface (like gases), the Absorptivity = 0 Reflectivity = 0 All of these Transmissivity = 1 Absorptivity = 0 Reflectivity = 0 All of these Transmissivity = 1 ANSWER DOWNLOAD EXAMIANS APP
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 Giving the surface a mirror finish Roughening the surface Painting the surface black Painting the surface white (with aluminium paint) Giving the surface a mirror finish Roughening the surface Painting the surface black Painting the surface white (with aluminium paint) ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A tank painted with which of the following coloured paints, would heat up maximum by radiation from sun? Yellow paint Grey paint White paint Black paint Yellow paint Grey paint White paint Black paint ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer The thermal efficiency of a reversible heat engine operating between two given thermal reservoirs is 0.4. The device is used either as a refrigerator or as a heat pump between the same reservoirs. Then the coefficient of performance as a refrigerator (COP)R and the co-efficient of performance as a heat pump (COP)HP are (COP)R = (COP)HP = 2.5 (COP)R = (COP)HP = 0.6 (COP)R = 1.5; (COP)HP = 2.5 (COP)R = 2.5; (COP)HP = 1.5 (COP)R = (COP)HP = 2.5 (COP)R = (COP)HP = 0.6 (COP)R = 1.5; (COP)HP = 2.5 (COP)R = 2.5; (COP)HP = 1.5 ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Which of the following situations can be approximated to a steady state heat transfer system? Boiling brine kept in open vessel when the bottom surface temperature of the vessel is maintained constant at 180°C A sub-cooled refrigerant liquid at 8°C flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmosheric air at 35°C 10 kg of dry saturated steam at 8 kgf/cm² flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C Boiling brine kept in open vessel when the bottom surface temperature of the vessel is maintained constant at 180°C A sub-cooled refrigerant liquid at 8°C flowing at the rate of 6 Kg/minute through a copper pipe exposed to atmospheric air at 35°C A red hot steel slab (having outside surface temperature as 1300°C) exposed to the atmosheric air at 35°C 10 kg of dry saturated steam at 8 kgf/cm² flowing through a short length of stainless steel pipe exposed to atmospheric air at 35°C ANSWER DOWNLOAD EXAMIANS APP
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