For an ideal black body Reflectivity = 1 Absorptivity = 1 Emissivity = 0 Transmissivity = 1 TRUE ANSWER : ? YOUR ANSWER : ?
The purpose of providing a 'catchall' in the vapor line of an evaporator is to Arrest the entrained liquid Regulate the vapor flow Vent the non-condensible gases Create vacuum TRUE ANSWER : ? YOUR ANSWER : ?
In thermal radiation for a black body (where, ε is emissivity and α is absorptivity) α = 1; ε = 1 α ≠ 1, ε = 1 α = 1; ε ≠ 1 α ≠ 1, ε ≠ 1 TRUE ANSWER : ? YOUR ANSWER : ?
Walls of a cubical oven are of thickness l, and they are made of material of thermal conductivity k. The temperature inside the oven is 100°C and the inside heat transfer co-efficient is 3k/l. If the wall temperature on the outside is held at 25°C, what is the inside wall temperature in degree centigrade? 43.75 48.25 81.25 35.5 TRUE ANSWER : ? YOUR ANSWER : ?
LMTD can't be used as such without a correction factor for the All of these Condensation of mixed vapour in a condenser Baffled heat exchanger Multipass heat exchanger TRUE ANSWER : ? YOUR ANSWER : ?
Electro-magnetic spectrum range, which is important for radiation varies from __________ microns. 0.5 to 50 100 to 1000 10 to 100 1 to 100 TRUE ANSWER : ? YOUR ANSWER : ?
Value of Nusselt number [Nu = (hD/k)] for the heat transfer by conduction from a droplet or a spherical particle to a surrounding stagnant film is 100 2 10 0.5 TRUE ANSWER : ? YOUR ANSWER : ?
While the total emissivity of a perfect black body is unity, the same for a real body is >1 0 between 0 and 1 1 TRUE ANSWER : ? YOUR ANSWER : ?
Extremely large or small volumes of fluids are generally best routed through the shell side of a shell and tube heat exchanger, because of the High heat transfer co-efficient Low pressure drop Less corrosion problems Flexibility possible in the baffle arrangement TRUE ANSWER : ? YOUR ANSWER : ?
In the free convection regime of pool boiling, the heat flux is proportional to Δt5/4 Δt Δt2 Δt1/2 TRUE ANSWER : ? YOUR ANSWER : ?