Q. Absorptivity of a perfect black body is unity. Which of the following has maximum absorptivity ?

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Q. At what value of Prandtl number, the hydrodynamic and thermal boundary layers of a fluid flowing over a heated plate will be identical ?

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Q. Fourier's law of heat conduction applies to __________ surfaces.

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Q. __________ chart is known as transient heat conduction chart.

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Q. In which mode of heat transfer, the Biot number is important ?

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Q. __________ paint has the minimum absorption co-efficient.

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Q. Asymptotic conditions is reached, when for a fluid flowing in laminar flow through a long tube

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Q. 1000 kg of wet solids are to be dried from 60% to 20% moisture (by weight). The mass of moisture removed in kg is

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Q. Which is the most suitable for the con-certration of highly concentrated solution?

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Q. The purpose of floating head in a heat exchanger is to

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Q. 1000 Kg of liquid at 30°C in a well stirred vessel has to be heated to 120°C, using immersed coils carrying condensing steam at 150°C. The area of the steam coils is 1.2 m² and the overall heat transfer co-efficient to the liquid is 1500 W/m².°C. Assuming negligible heat loss to the surrounding and specific heat capacity of the liquid to be 4 kJ/kg.°C, the time taken for the liquid to reach desired temperature will be

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Q. Overall thermal resistance for conductive heat transfer through a series of flat resistances is equal to the

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Q. Double pipe heat exchangers are preferably useful, when

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Q. Removal of __________ heat is involved in the condensation of a vapor under saturated conditions.

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Q. In a shell and tube heat exchanger, putting a longitudinal baffle across the shell, forces the shell side fluid to pass __________ through the heat exchanger.

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Q. When the ratio of the Grashoff number and to the square of Reynolds number is one, the dominant mechanism of heat transfer is

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Q. The purpose of providing bleed points in the evaporator is to

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Q. Water always boils when its

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Q. A multiple effect evaporator as compared to a single effect evaporator of the same capacity has

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Q. When does the heat generated by fluid friction becomes appreciable compared to the heat transferred between the fluids ?

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