Heat and Mass Transfer The time constant of a thermocouple is Determined by the time taken to reach 100°C from 0°C The time taken to attain the final temperature to be measured The time taken to attain 63.2% of the value of initial temperature difference The time taken to attain 50% of the value of initial temperature difference Determined by the time taken to reach 100°C from 0°C The time taken to attain the final temperature to be measured The time taken to attain 63.2% of the value of initial temperature difference The time taken to attain 50% of the value of initial temperature difference ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer When heat is transferred from one particle of hot body to another by actual motion of the heated particles, it is referred to as heat transfer by Conduction and convection Conduction Radiation Convection Conduction and convection Conduction Radiation Convection ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Which of the following is a case of steady state heat transfer? Heating of building in winter None of these I.C. engine Air preheaters Heating of building in winter None of these I.C. engine Air preheaters ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is 66.7°C 60°C 40°C 20°C 66.7°C 60°C 40°C 20°C ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Stefan's law, the total radiation from a black body per second per unit area is proportional to T5 Absolute temperature T T2 T5 Absolute temperature T T2 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, body will be transparent when (Where a = absorptivity, p = reflectivity, x = transmissivity) P=1, x = 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, x = 0, and a = 0 P = 0, x= 1, and a = 0 X = 0, a + p = 1 P = 0, x = 0 and a = 1 ANSWER DOWNLOAD EXAMIANS APP