Heat Transfer
Dropwise condensation of steam on cooling surface is promoted

An oily surface
Only in presence of air
None of these
When both the steam and the tube are clean

ANSWER DOWNLOAD EXAMIANS APP

Heat Transfer
Condensing film co-efficient for steam on horizontal tubes ranges from 5000 to 15000 Kcal/hr.m² .°C. Condensation of vapor is carried out inside the tube in a shell and tube heat exchanger, when the

Lower pressure drop through the exchanger is desired
Temperature of the incoming vapor is very high
Condensate is corrosive in nature
Higher condensing film co-efficient is desired

ANSWER DOWNLOAD EXAMIANS APP

Heat Transfer
Heat transfer by conduction results due to the transfer of free electrons, kinetic energy & vibrational energy from one molecule to another. Conduction heat transfer can not take place

Between two bodies not in physical contact with each other
Between two bodies in physical contact with each other
Both B & C
From one part of a body to the another part of the same body

ANSWER DOWNLOAD EXAMIANS APP