Q. The atmospheric air at dry bulb temperature of 15°C enters a heating coil maintained at 40°C. The air leaves the heating coil at 25°C. The by-pass factor of the heating coil is

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Q. An infinite parallel planes with emissivities e1 and e2, the interchange factor for radiation from surface 1 to surface 2 is given by

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Q. R-12 is generally preferred over R-22 in deep freezers since

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Q. The temperature of air recorded by a thermometer, when its bulb is surrounded by a wet cloth exposed to the air, is called

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Q. During sub-cooling, sensible heat from a liquid refrigerant is removed.

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Q. The expression is used for calculating relative humidity.

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Q. If the energy radiated per second per sq. cm. of the surface for wave lengths lying between λ, and λ + dλ is represented by (eλ.dλ), then eλ is called

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Q. The wet bulb depression indicates __________ humidity of the air.

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Q. The refrigerant widely used in domestic refrigerators is

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Q. When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmittivity (τ) = 0, then the body is said to be a

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Q. Prandtl number (PN) is given by PN = μ.cp/k.

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Q. In a vapour compression system, the condition of refrigerant before passing through the condenser is

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Q. A composite slab has two layers of different materials with thermal conductivities k1 and k2. If each layer has the same thickness, then the equivalent thermal conductivity of the slab will be

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Q. The critical temperature is the temperature

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Q. The evaporator changes the low pressure liquid refrigerant from the expansion valve into

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Q. For air conditioning the operation theatre in a hospital, the percentage of outside air in the air supplied is

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Q. In case ofsensible cooling of air, the coil efficiency is given by

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Q. The cooling system used for supersonic aircrafts and rockets is

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Q. Which of the following statement is correct?

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Q. The desirable property of a refrigerant is

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