Refrigeration and Air Conditioning

This is an MCQ-based quiz on the topic of Refrigeration and Air Conditioning.

This includes BRIEF HISTORY OF REFRIGERATION, Vapor-Absorption Machine of Ferdinand Carre, Applications of Refrigeration and Air Conditioning, and many more.

Start Quiz

Nusselt number (NN) is given by

NN = hl/k NN = μ cp/k NN = ρ V l /μ NN = V²/t.cp

In case of sensible heating of air, the coil efficiency is given by (where B.P.F. = Bypass factor)

B.P.F. - 1 1 - B. P.F. 1/ B.P.F. 1 + B.P.F.

The undesirable property of a refrigerant is

Non-toxic Non-flammable Non-explosive High boiling point

The desirable property of a refrigerant is

Low boiling point High critical temperature High latent heat of vaporisation All of these

The operating pressure for refrigerating units using R-12 as a refrigerant is

2 bar 8 bar 15 bar 30 bar

Which of the following is the material of tubes used for shell and tube condenser in ammonia refrigeration system?

Copper Steel Brass Aluminum

In mechanical refrigeration system, the refrigerant has the maximum temperature

In evaporator Before expansion valve Between compressor and condenser Between condenser and evaporator

In a vapour compression cycle, the refrigerant immediately after expansion valve is

Liquid Sub-cooled liquid Saturated liquid Wet vapour

A human body feels comfortable when the heat produced by the metabolism of human body is equal to the

Heat dissipated to the surroundings Heat stored in the human body Sum of (A) and (B) Difference of (A) and (B)

The domestic refrigerator uses following type of compressor

Centrifugal Axial Miniature sealed unit Piston type reciprocating

The coefficient of performance of Heat Pump is always _________ one.

Equal to Less than Greater than None of these

How is the refrigerant used in the Air refrigeration cycle?

In the compressor In the condenser Directly in contact Not used at all

Which of the following refers to the term C.O.P. of refrigeration?

Cooling for Performance Coefficient of Performance Capacity of Performance Co-efficient of Plant

Which of the following is NOT the advantages of using a closed Air Refrigeration system?

Compact in construction Lower coefficient of performance Lighter in weight Environmental Friendly

Which of the following is the S.I. unit to measure pressure in refrigeration?

Bar Newton Joule Pascal

If the Coefficient of performance of a heat pump is 5, then what is the value of the Coefficient of performance of the refrigerator operating under the same conditions?

0.2 3 4 6

How is the cascade system achieved?

VCR system in a parallel combination VCR system in a series combination VAR system in a series combination VAR system in a parallel combination

In which of the following Capillary tube is used in as an expansion device?

Room air conditioners Water coolers Domestic refrigerators All of the mentioned

Which of the following uses natural convection air-cooled condensers?

High capacity room air conditioners Industrial air conditioners Domestic refrigerators High capacity water coolers

Which of the following is the main disadvantage of natural refrigeration methods?

Natural refrigeration methods are dependent on local conditions

Natural refrigeration methods are not environment friendly

Natural refrigeration methods are expensive

Natural refrigeration methods are poisonous