Which of the following is the most controlling factor for the rate of bubble detachment from the hot solid surface? Liquid density Interfacial tension Hot surface temperature Liquid viscosity TRUE ANSWER : ? YOUR ANSWER : ?
In the equation Q = UAΔt; Δt is Geometric mean temperature difference Logarithmic mean temperature difference Arithmetic mean temperature difference The difference of average bulk temperatures of hot and cold fluids TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following has the minimum absorptivity? Iron plates Refractory bricks Aluminium foil Coal dust TRUE ANSWER : ? YOUR ANSWER : ?
Solid angle subtended by the finite surface at the radiating element is called the angle of vision expressed in terms of radians proportional to the square of the distance between surfaces called the view factor. TRUE ANSWER : ? YOUR ANSWER : ?
While the total emissivity of a perfect black body is unity, the same for a real body is between 0 and 1 >1 1 0 TRUE ANSWER : ? YOUR ANSWER : ?
Which is the most suitable for the concentration of foamy & frothy liquors? Open pan evaporator None of these Long tube vertical evaporator Agitated film evaporator TRUE ANSWER : ? YOUR ANSWER : ?
Conduction occurs in the buffer zone for a fluid flowing through a heated pipe, only when Prandtl number is < 1 >1 0.1 L TRUE ANSWER : ? YOUR ANSWER : ?
The dimensionless group in mass transfer that is equivalent to Prandtl number in heat transfer is Sherwood number Nusselt number Stanton number Schmidt number TRUE ANSWER : ? YOUR ANSWER : ?
Electromagnetic radiations propagate in vacuum with a velocity of __________ metre/second. 3 x l05 3 x l012 3 x l08 3 x l010 TRUE ANSWER : ? YOUR ANSWER : ?
Open pan evaporators are preferred to be used, when the solution to be concentrated is Highly viscous Salty Corrosive Scaling TRUE ANSWER : ? YOUR ANSWER : ?