Heat Transfer For condensation of pure vapors, if the heat transfer co-efficients in filmwise and drop-wise condensation are respectively hf and hd, then hf = hd hf > hd hf < hd hf could be greater or smaller than hd hf = hd hf > hd hf < hd hf could be greater or smaller than hd ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer The average heat transfer co-efficient for laminar film condensation on vertical surface is inversely proportional to (where, ΔT = Temperature drop across condensate film ) (ΔT)2 ΔT (ΔT)1/4 None of the listed here (ΔT)2 ΔT (ΔT)1/4 None of the listed here ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer Thermal conductivity of a conducting solid material depends upon its porosity both temperature & porosity None of the listed here temperature porosity both temperature & porosity None of the listed here temperature ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer A steel sphere of radius 0.1 m at 400°K is immersed in an oil at 300°K. If the centre of the sphere reaches 350°K in 20 minutes, how long will it take for a 0.05 m radius steel sphere to reach the same temperature (at the centre) under identical conditions ? Assume that the conductive heat transfer co-efficient is infinitely large. 5 minutes 10 minutes 40 minutes 20 minutes 5 minutes 10 minutes 40 minutes 20 minutes ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer With increase in temperature, the thermal conductivity of most liquids Remains same Decreases Increases First increases upto a certain temperature and then becomes constant Remains same Decreases Increases First increases upto a certain temperature and then becomes constant ANSWER DOWNLOAD EXAMIANS APP
Heat Transfer In a cooling tower, water becomes cool by Heat transfer to surroundings Loosing latent heat Loosing sensible heat Vaporisation due to heat loss to air Heat transfer to surroundings Loosing latent heat Loosing sensible heat Vaporisation due to heat loss to air ANSWER DOWNLOAD EXAMIANS APP