Thermal conductivities of most of the liquids _______________ with rise in temperature?

Related Mcqs:

What is the geometric mean of two heat transfer areas A1 and A2 ?

A. √(A1 . A2) B. √(A1 + A2) C. ½ √(A1 . A2) D. 2 √(A1 . A2)...

Overall heat transfer co-efficient of a particular tube is U1. If the same tube with some dirt deposited on either side has coefficient U2, then_________________?

A. U1 = U2 B. U2 > U1 C. U1 > U2 D. U1 = dirt factor – U2...

It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of vaporisation is 2100 kJ/kg and the specific heat of the solution is 4 kJ/kg.K. The rate at which the heat has to be supplied in (kJ/min) to the evaporator is____________________?

A. 3.06 × 105 B. 6.12 × 105 C. 7.24 × 105 D. 9.08 × 105...

A composite flat wall of a furnace is made of two materials ‘A’ and ‘B’. The thermal conductivity of ‘A’ is twice of that of material ‘B’, while the thickness of layer of ‘A’ is half that of B. If the temperature at the two sides of the wall are 400 and 1200°K, then the temperature drop (in °K) across the layer of material ‘A’ is________________?

A. 125 B. 133 C. 150 D. 160...

Sensible heat of hot industrial flue gases cannot be recovered by a/an________________?

A. Economiser B. Regenerator C. Ceramic recuperator D. None of these...