Q. A hot liquid is kept in a big room. The logorithm of the numerical value of the temperature difference between the liquid and the room is plotted against time. The plot will be very nearly a/an

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Q. Radiation heat transfer rates does not depend upon the

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Q. Which of the following is correct ?

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Q. Convective heat transfer, in which heat is transferred by movement of warmed matter is described by

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Q. As the difference between the wall temperature and bulk temperature increases, the boiling heat transfer co-efficient

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Q. Heat transfer rate per unit area is called

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Q. Log mean temperature difference (LMTD) cannot be used, if

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Q. The critical radius 'r' of insulation on a pipe is given by

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Q. As per Kirchoffs law, the ratio of the total radiating power to the absorptivity of a body depends on the

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Q. If the baffle spacing in a shell and tube heat exchanger increases, then the Reynolds number of the shell side fluid

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Q. The heat transfer by radiation from a mild steel surface is to be reduced by reducing the emissivity of the surface. This can be best achieved by

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Q. __________ paint has the maximum absorption coefficient.

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Q. Which of the following is unimportant in forced convection ?

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Q. Steam is to be condensed in a shell and tube heat exchanger, 5 m long with a shell diameter of 1 m. Cooling water is to be used for removing the heat. Heat transfer co-efficient for the cooling water, whether on shell side or tube side is the same. The best arrangement is

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Q. In a multiple effect evaporator, the effect of boiling point elevation is to

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Q. Dropwise condensation occurs on __________ surfaces.

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Q. Heat transfer efficiency leading of energy conservation in a heat exchanger can be achieved by

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Q. Trap is used to remove __________ from steam pipe lines.

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Q. 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

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Q. Tube pitch is the __________ of tube diameters and the clearances.

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