Heat and Mass Transfer If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called Emissivity None of these Emissive power Absorptive power Emissivity None of these Emissive power Absorptive power ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Total emissivity of polished silver compared to black body is Very much lower Higher Same More or less same Very much lower Higher Same More or less same ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer The ratio of surface convection resistance to the internal conduction resistance is known as Stanton number Prandtl number Grashoff number Biot number Stanton number Prandtl number Grashoff number Biot number ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Thermal conductivity of air at room temperature in kcal/m hr °C is of the order of 0.002 0.1 0.01 0.02 0.002 0.1 0.01 0.02 ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Metals are good conductors of heat because They contain free electrons Their atoms collide frequently They have high density Their atoms are relatively far apart They contain free electrons Their atoms collide frequently They have high density Their atoms are relatively far apart ANSWER DOWNLOAD EXAMIANS APP
Heat and Mass Transfer Emissivity of a white polished body in comparison to a black body is Lower Higher Depends upon the shape of body Same Lower Higher Depends upon the shape of body Same ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS