Q. According to Stefan-Boltzmann law, the total radiation from a black body per second per unit area is directly proportional to the

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Q. A good refrigerant should have

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Q. The thermal diffusivity for gases is generally __________ those for liquids.

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Q. In a shell and coil condenser, water flows in the shell and the refrigerant in the coil.

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Q. In a saturated air-water vapour mixture, the

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Q. Dew point temperature corresponds to the saturation temperature of vapour at its partial pressure.

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Q. The capillary tube is not used in large capacity refrigeration systems because

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Q. The ratio of emissive power of a body to the emissive power of a perfectly black body is called emissivity.

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Q. The thermostatic expansion valve operates on the changes in the

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Q. In a vapour compression system, the condition of refrigerant before entering the expansion or throttle valve is

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Q. The freezing point of R-12 is

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Q. The refrigerant supplied to a compressor must be

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Q. The unit of thermal diffusivity is

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Q. The superheated vapour region, in a pressure enthalpy chart, is represented by the space

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Q. The minimum temperature to which water can be cooled in a cooling tower is

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Q. The index which corelates the combined effects of air temperature, relative humidity and air velocity on the human body, is known as

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Q. The ratio of Nusselt number and the product of Reynold's number and Prandtl number is equal to

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Q. The alignment circle is marked on the psychrometric chart at

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Q. The operating temperature of a cold storage is - 2° C. The heat leakage from the surrounding is 30 kW for the ambient temperature of 40° C. The actual C.O.P. of refrigeration plant used is one fourth that of ideal plant working between the same temperatures. The power required to drive the plant is

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Q. In chemical dehumidification process,

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