Heat and Mass Transfer Which of the following would lead to a reduction in thermal resistance? In convection, stirring of the fluid and cleaning the heating surface. In radiation, increasing the temperature and reducing the emissivity. All of these In conduction, reduction in the thickness of the material and an increase in thermal conductivity. In convection, stirring of the fluid and cleaning the heating surface. In radiation, increasing the temperature and reducing the emissivity. All of these In conduction, reduction in the thickness of the material and an increase in thermal conductivity. ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Two balls of same material and finish have their diameters in the ratio of 2: 1 and both are heated to same temperature and allowed to cool by radiation. Rate of cooling by big ball as compared to smaller one will be in the ratio of 0.084027777777778 0.16736111111111 0.043055555555556 0.042361111111111 0.084027777777778 0.16736111111111 0.043055555555556 0.042361111111111 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of water _________ with rise in temperature. Decreases Increases May increase or decrease depending upon temperature Remain same Decreases Increases May increase or decrease depending upon temperature Remain same ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer According to Kirchoff's law, the ratio of emissive power to absorptivity for all bodies is equal to the emissive power of a Black body Brilliant white polished body Grey body Red hot body Black body Brilliant white polished body Grey body Red hot body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Radiation is the process of heat transfer in which heat flows from a ________, in a straight line, without affecting the intervening medium. Smaller body to larger body Cold body to hot body Hot body to cold body Larger body to smaller body Smaller body to larger body Cold body to hot body Hot body to cold body Larger body to smaller body ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Depending on the radiating properties, a body will be black when (Where a = absorptivity, p = reflectivity, X = transmissivity.) P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 X = 0, a + p = 0 P = 0, x = 1 and a = 0 P = 0, x = 0 and a = 1 P= 1, T = 0 and a = 0 X = 0, a + p = 0 ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS