A capillary tube is employed in a refrigeraton cycle to
Produce cooling effect
Convert refrigerant from liquid to vapour state
Control the temperature of refrigerated space
Control the flow of refrigerant
In a vopour compression refrigeration cycle, the flow of refrigeration is regulated through
Speed of the compressor
Expansion valve
Amount of heat absorbed in the evaporator
Pressure of refrigerant at exit from the compressor
In a vapour compression refrigeration system, a throttle valve is used in place of expander because it
It leads to significant cost reduction
It considerably reduces the system work
Positive work in isentropic expansion of liquid is very small
Improves COP
Identify the purpose served by receiver fitted in a refrigeration unit:
To reduce the work input to compressor
To conserve heat
To allow for variation of load
To dampen the noise generated by moving parts of the compressor
Which of the following aspects is not true in the context of dry compression in a vapour compression refrigeration cycle?
Increase in refrigerating effect
Increase in power consumption
Improvement in coefficient of performance
Complete evaporation in the evaporator
Which is usually the costliest item in a refrigeration system?
Condenser
Capillary tube
Compressor
Evaporator
Which of the following type of compressor is generally used in domestic refrigerator
Axial
Centrifugal
Mixed flow
In a hermetically sealed compressor unit,
Both the motor and compressor are sealed
Only compressor is sealed
Only motor is sealed
Either motor or compressor is sealed
Which type of valve is used in a reciprocating refrigeration compressor?
Rotary valve
Poppet valve
Ring plate valve
Glob valve
Which of the following components in a vapour absorption plant is a substitute for the compressor of the vapour compression system?
Absorber
Heat exchanger and generator
Aqua pump and generator
Absorber, aqua pump and generator
In ammonia absorption system, there is transfer of heat from
Weak ammonia solution to strong ammonia solution
Strong solution to ammonia vapour
Ammonia vapour to strong solution
Weak solution to ammonia vapour
Which of the following components is common between vapour compression and vapour absorption systems?
Absorber
Generator
Condenser
Rectifier
Aqua ammonia solution used in vapour absorption refrigeration system is a solution of ammonia in
Water
Hydrogen
Lithium bromide
Carbon tetrachloride
In aqua-ammonia and Li-Br water absorption refrigeration systems, the refrigerants are respectively
Water and water
Water and Li-Br
Ammonia and Li-Br
Ammonia and water
The degree of saturation is defined as
Mass of water vapour per unit volume of air-water vapour mixture
Mass of water vapour per kg of dry air in the mixture
The ratio of mass of water vapour in a given volume of moist air to the mass of water vapour in the same volume of saturated air at the same temperature ad pressure
/
Absolute humidity
Humidity ratio
Relative humidity
Degree of saturation