Test Bank: Modern Refrigeration and Air
Conditioning
absolute zero - AnswersIs the temperature where molecular motion stops
four basic parts of a mechanical refrigeration system - AnswersCompressor, condenser,
refrigerant control, and evaporator
The first of the sealed or hermetic automatic refrigeration units introduced in 1928 -
AnswersThe Monitor Top
The Brittish thermal Unit - AnswersThe U.S. conventional unit of heat
How does heat flow? - AnswersFrom warm to cold
Cold - AnswersLow temperature or lack of heat
The correct refrigerator temperature for fresh food is - Answers35 to 45 degrees Fahrenheit
What measures the heat intensity of a subject? - AnswersTemperature
What is the thermal of an atom multiplied by the number of atoms affected? - AnswersHeat
What two temperatures determine the calibration of a thermometer? - AnswersThe
temperature of melting ice, and the temperature of boiling water.
The are 180 degrees of space between what? - AnswersMelting ice (32 deg) and boiling water
(212 deg) Fahrenheit.
,What term means a difference? - AnswersDelta
What is the force per unit area, and is expressed in pounds per square inch (psi) -
AnswersPressure
What is the normal pressure of the atmosphere at sea level? - Answers14.7 psi
Operation of a refrigeration system depends mainly on what? - AnswersPressure differences in
the system
What Law stated that "Pressure applied upon a confined fluid is transmitted equally in all
directions. - AnswersPascal's Law
A reading of 0 psi on the gauge is equal to? - Answers14.7 psia
What gauge is used for measuring below atmospheric pressure? - AnswersA mercury gauge
Absolute pressure equals - AnswersGauge pressure plus atmospheric pressure
Substances exist in 3 states depending on what? - AnswersTheir temperature, pressure, and
heat content
Objects which float on water have a specific gravity of? - AnswersLess than 1
Objects which sink in water have a specific gravity of? - AnswersGreater than one
, BTU (British Thermal Unit) - AnswersIs the amount of heat required to raise the Temperature of
1 pound of water 1 degree Fahrenheit
Joule - AnswersA very small unit of heat
Latent heat - AnswersHeat which brings about a change of state with no change in temperature.
Sensible heat - AnswersHeat which causes a change in temperature in a substance.
The heat energy absorbed when 2000 pounds of ice melts during one 24hr day - AnswersTon of
refrigeration effect
Heat may be transferred from one body to another by what 3 methods? - AnswersRadiation,
convection, and conduction
This substance goes directly from a solid to a vapor? - AnswersDry ice via (sublimation)
Enthalpy - AnswersThe measure of heat content in a substance
What is the purpose of the refrigerant control - AnswersTo allow refrigerant to flow from the
the liquid receiver (high side) into the evaporator (low side).
Do you push or pull on a wrench? - AnswersPull, to prevent slippage. (Safety note)
Why should tubing be bent? - AnswersSo that it does not place strain on the fittings once it's
installed
Conditioning
absolute zero - AnswersIs the temperature where molecular motion stops
four basic parts of a mechanical refrigeration system - AnswersCompressor, condenser,
refrigerant control, and evaporator
The first of the sealed or hermetic automatic refrigeration units introduced in 1928 -
AnswersThe Monitor Top
The Brittish thermal Unit - AnswersThe U.S. conventional unit of heat
How does heat flow? - AnswersFrom warm to cold
Cold - AnswersLow temperature or lack of heat
The correct refrigerator temperature for fresh food is - Answers35 to 45 degrees Fahrenheit
What measures the heat intensity of a subject? - AnswersTemperature
What is the thermal of an atom multiplied by the number of atoms affected? - AnswersHeat
What two temperatures determine the calibration of a thermometer? - AnswersThe
temperature of melting ice, and the temperature of boiling water.
The are 180 degrees of space between what? - AnswersMelting ice (32 deg) and boiling water
(212 deg) Fahrenheit.
,What term means a difference? - AnswersDelta
What is the force per unit area, and is expressed in pounds per square inch (psi) -
AnswersPressure
What is the normal pressure of the atmosphere at sea level? - Answers14.7 psi
Operation of a refrigeration system depends mainly on what? - AnswersPressure differences in
the system
What Law stated that "Pressure applied upon a confined fluid is transmitted equally in all
directions. - AnswersPascal's Law
A reading of 0 psi on the gauge is equal to? - Answers14.7 psia
What gauge is used for measuring below atmospheric pressure? - AnswersA mercury gauge
Absolute pressure equals - AnswersGauge pressure plus atmospheric pressure
Substances exist in 3 states depending on what? - AnswersTheir temperature, pressure, and
heat content
Objects which float on water have a specific gravity of? - AnswersLess than 1
Objects which sink in water have a specific gravity of? - AnswersGreater than one
, BTU (British Thermal Unit) - AnswersIs the amount of heat required to raise the Temperature of
1 pound of water 1 degree Fahrenheit
Joule - AnswersA very small unit of heat
Latent heat - AnswersHeat which brings about a change of state with no change in temperature.
Sensible heat - AnswersHeat which causes a change in temperature in a substance.
The heat energy absorbed when 2000 pounds of ice melts during one 24hr day - AnswersTon of
refrigeration effect
Heat may be transferred from one body to another by what 3 methods? - AnswersRadiation,
convection, and conduction
This substance goes directly from a solid to a vapor? - AnswersDry ice via (sublimation)
Enthalpy - AnswersThe measure of heat content in a substance
What is the purpose of the refrigerant control - AnswersTo allow refrigerant to flow from the
the liquid receiver (high side) into the evaporator (low side).
Do you push or pull on a wrench? - AnswersPull, to prevent slippage. (Safety note)
Why should tubing be bent? - AnswersSo that it does not place strain on the fittings once it's
installed
