Q.1
It is desired to condition the outside air from 70% relative humidity and 45° C dry bulb temperature to 50% relative humidity and 25° C dry bulb temperature (room condition). The practical arrangement will be
Q.2
In a bootstrap air evaporative cooling system, the evaporator is provided
Q.3
The refrigerant for a refrigerator should have
Q.4
The difference between dry bulb temperature and wet bulb temperature, is called
Q.5
The difference between dry bulb temperature and dew point temperature, is called
Q.6
The conditioned air supplied to the room must have the capacity to take up
Q.7
In a saturated air-water vapour mixture, the
Q.8
The pressure at the inlet of a refrigerant compressor is called
Q.9
The pressure at the outlet of a refrigerant compressor is called
Q.10
For obtaining high COP, the pressure range of compressor should be
Q.11
Most thermostatic expansion valves are set for a superheat of
Q.12
For large tonnage (more than 200 TR) air-conditioning applications, the compressor recommended is
Q.13
One tonne of refrigeration (1TR) means that the heat removing capacity is
Q.14
Refrigeration in aeroplanes usually employs the following refrigerant
Q.15
In vapour compression cycle using NH₃ as refrigerant, initial charge is filled at
Q.16
If a heat pump cycle operates between the condenser temperature of +27°C and evaporator temperature of -23°C, then the Carnot COP will be
Q.17
Absorption system normally uses the following refrigerant
Q.18
When the lower temperature of a refrigerating machine is fixed, then the coefficient of performance can be improved by
Q.19
The evaporator changes the low pressure liquid refrigerant from the expansion valve into
Q.20
Vertical lines on pressure-enthalpy chart show constant
Q.21
A vapour absorption refrigerator uses _________ as a refrigerant.
Q.22
An infinite parallel planes with emissivities e₁ and e₂, the interchange factor for radiation from surface 1 to surface 2 is given by
Q.23
A one tonne refrigerating machine means that
Q.24
The coefficient of performance is the ratio of the refrigerant effect to the
Q.25
In refrigerator, liquid receiver is required between condenser and flow controlling device, if quantity of refrigerant for system is
Q.26
Which of the following statement is correct for ammonia as a refrigerant?
Q.27
When the air is passed through an insulated chamber having sprays of water maintained at a temperature higher than the dew point temperature of entering air but lower than its dry bulb temperature, then the air is said to be
Q.28
The unit of thermal diffusivity is
Q.29
Pressure of water vapour is given by
Q.30
Ammonia is
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