Q. The emissivity of a polished silver body is __________ as compared to black body.

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Q. In a pressure enthalpy chart, the space between the saturated liquid line and saturated vapour line, represents sub-cooled liquid region.

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Q. R-11 has the highest critical point temperature.

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Q. The ratio of heat extracted in the refrigerator to the workdone on the refrigerant is called

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Q. The boiling point of ammonia is

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Q. The by-pass factor (B. P. F.) in case of sensible heating of air is (Where td1 = Dry bulb temperature of air entering the heating coil, td2 = Dry bulb temperature of air leaving the heating coil, and td3 = Dry bulb temperature of heating coil)

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Q. The refrigerant used for absorption refrigerators working on heat from solar collectors is a mixture of water and

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Q. In a black body, all radiations are rejected.

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Q. Most air cooled condensers are designed to operate with a temperature difference of

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Q. A Bell Coleman refrigerator working on dense air system as compared to open air system, for the same range of temperature, results in higher coefficient of performance.

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Q. The ratio of surface convection resistance to the internal conduction resistance is known as

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Q. Relative humidity is given by (where pv = Partial pressure of water vapour, pb = Barometric pressure, ps = Pressure of saturated air, pd = Pressure at dry bulb temperature, pw = Saturation pressure corresponding to wet bulb temperature, and μ = Degree of saturation)

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Q. Kirchhoff's law states that

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Q. Dew point temperature is the temperature of air recorded by a thermometer, when the moisture present in it begins to condense.

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Q. Planck's law holds good for all coloured bodies.

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Q. In mechanical refrigeration system, the refrigerant has the maximum temperature

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Q. The capacity of a domestic refrigerator is in the range of

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Q. The condition of refrigerant after passing through the condenser in a vapour compression system is

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Q. The leakage in a refrigeration system using freon is detected by

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Q. The product of Reynolds number and Prandtl number is known as

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