Heat and Mass Transfer Thermal conductivity of air with rise in temperature May increase or decrease depending on temperature Remain constant Decreases Increases May increase or decrease depending on temperature Remain constant Decreases Increases ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two long parallel surfaces each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation heat exchange between them. It is desired to reduce 75% of the radiant heat transfer by inserting thin parallel shields of emissivity 1 on both sides. The number of shields should be Three Four Two One Three Four Two One ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Conduction is a process of heat transfer From one particle of the body to another without the actual motion of the particles None of these From one particle of the body to another by the actual motion of the heated particles From a hot body to a cold body, in a straight line, without affecting the intervening medium From one particle of the body to another without the actual motion of the particles None of these From one particle of the body to another by the actual motion of the heated particles From a hot body to a cold body, in a straight line, without affecting the intervening medium ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According of Kirchhoff's law Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body Radiant heat is proportional to fourth power of absolute temperature Emissive power and absorptivity are constant for all bodies Emissive power depends on temperature Ratio of emissive power to absorptive power for all bodies is same and is equal to the emissive power of a perfectly black body 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 = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 X = 0, a + p = 1 P = 0, x= 1, and a = 0 P = 0, x = 0 and a = 1 P=1, x = 0, and a = 0 X = 0, a + p = 1 P = 0, x= 1, and a = 0 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The heat transfer takes place according to Zeroth law of thermodynamics Kirchhoff's law Second law of thermodynamics First law of thermodynamics Zeroth law of thermodynamics Kirchhoff's law Second law of thermodynamics First law of thermodynamics ANSWER DOWNLOAD EXAMIANS APP
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