REFRIGERATION TESTED EXAM
QUESTIONS WITH VERIFIED
ANSWERS
The unit used to measure the amount of heat removed from a substance is the____. -
Answer- BTU
The boiling point of a liquid:
A. Increases at an elevation above sea level
B. Depends on the radiation
C. Depends on the absolute pressure
D. Depends on the specific heat of the substance - Answer- Depends on the absolute
pressure
If the pressure exerted on a refrigerant in the vapor state remains constant, but it's
temperature above absolute zero is doubled, the volume of the vapor will be:
A. Reduced by 50%
B. Unchanged
C. Squared
D. Approximately doubled - Answer- Approximately doubled
When it object is refrigerated:
A. Some of its heat energy is destroyed
B. Heat is removed from it
C. More cooling is added
D. It's molecules move faster - Answer- Heat is removed from it
When a pound of water is heated from 32°F to 212°F it gains:
A. 970 BTU of latent heat
B. 144 BTU of latent heat
C. 180 BTU of sensible heat
D. The heat of fusion - Answer- 180 BTU of sensible heat
,Absolute zero is calculated to be____°F - Answer- -460°F
The amount of heat removed to lower the temperature of 15 lbs of water from 48°F to
39°F is: - Answer- 1btu x 15lbs = 15 | 48-39=9
9x15=135
135 BTU
A ton of refrigeration is equal to_____Btu/hr - Answer- 12,000
Three states of matter: - Answer- solid, liquid, gas
A pressure of 30 ft of water is equal to a pressure of: - Answer- .433 x 30 = 12.99
12.99psig
If a pressure gauge reads 5 PSIG at sea level elevation, the corresponding absolute
pressure is: - Answer- 5 + 14.7 = 19.7
19.7 psig
If the specific volume of a substance is 2.5ft 3/lb, find the weight of a cu.ft. Of the
substance - Answer- 0.4
Chapter 2: Elementary Refrigeration Methods - Answer-
The low side of a vapor compression cycle contains the:
A. Condenser
B. Evaporator
C. Compressor discharge line
D. Condenser and evaporator - Answer- Evaporator
A piece of ice weighs 20 Lbs and it's Pacific heat is 0.49. It will require_____Btu to heat
the piece of ice from 27°F to 31°F. - Answer- 31 - 27 = 4
4 x 20 = 80
80 x 0.49 = 39.2
39.2 BTUs
Of the following terms the largest amount in BTU for 1 pound of water is:
A. It's sensible heat
B. It's latent heat of fusion
C. It's latent heat of vaporization
, D. It's latent heat of melting - Answer- It's latent heat of vaporization
If the evaporator in a vapor compression cycle is not cold enough, it can be made colder
by:
A. Raising the evaporator pressure
B. Stopping the compressor temporarily
C. Lowering the evaporator pressure
D. Venting the refrigerant to the atmosphere - Answer- Lowering the evaporator
pressure
Calculate the amount of heat which will be absorbed when 15 pounds of solid
substance at a temperature of 30°F is changed to a liquid at 44°F - Answer-
The purpose of the condenser in the vapor compression cycle is to:
A. Save the refrigerant for reuse
B. Reduce the superheated vapor to evaporator temperature
C. Reduce the evaporator pressure
D. Lower the evaporator temperature - Answer- Save the refrigerant for re-use
In the vapor compression cycle, the compressor:
A. Heats the refrigerant vapor
B. Reduces evaporator pressure
C. Compresses the refrigerant vapor.
D. All of the above - Answer- Heats the refrigerant vapor
Reduces evaporator pressure
Compresses the refrigerant vapor.
Water can be made to boil at 50°F by:
A. Subcooling it to 50°F
B. Reducing the pressure to 14.7 psi absolute
C. Placing it under a high enough vacuum
D. Lowering the pressure to atmospheric pressure - Answer- Placing it under a high
enough vacuum
Chapter 3: Refrigerants - Answer-
An example of a halogen is:
A. Sulfur dioxide
B. Butane
C. Carbon dioxide
D. None of these - Answer- None of these
QUESTIONS WITH VERIFIED
ANSWERS
The unit used to measure the amount of heat removed from a substance is the____. -
Answer- BTU
The boiling point of a liquid:
A. Increases at an elevation above sea level
B. Depends on the radiation
C. Depends on the absolute pressure
D. Depends on the specific heat of the substance - Answer- Depends on the absolute
pressure
If the pressure exerted on a refrigerant in the vapor state remains constant, but it's
temperature above absolute zero is doubled, the volume of the vapor will be:
A. Reduced by 50%
B. Unchanged
C. Squared
D. Approximately doubled - Answer- Approximately doubled
When it object is refrigerated:
A. Some of its heat energy is destroyed
B. Heat is removed from it
C. More cooling is added
D. It's molecules move faster - Answer- Heat is removed from it
When a pound of water is heated from 32°F to 212°F it gains:
A. 970 BTU of latent heat
B. 144 BTU of latent heat
C. 180 BTU of sensible heat
D. The heat of fusion - Answer- 180 BTU of sensible heat
,Absolute zero is calculated to be____°F - Answer- -460°F
The amount of heat removed to lower the temperature of 15 lbs of water from 48°F to
39°F is: - Answer- 1btu x 15lbs = 15 | 48-39=9
9x15=135
135 BTU
A ton of refrigeration is equal to_____Btu/hr - Answer- 12,000
Three states of matter: - Answer- solid, liquid, gas
A pressure of 30 ft of water is equal to a pressure of: - Answer- .433 x 30 = 12.99
12.99psig
If a pressure gauge reads 5 PSIG at sea level elevation, the corresponding absolute
pressure is: - Answer- 5 + 14.7 = 19.7
19.7 psig
If the specific volume of a substance is 2.5ft 3/lb, find the weight of a cu.ft. Of the
substance - Answer- 0.4
Chapter 2: Elementary Refrigeration Methods - Answer-
The low side of a vapor compression cycle contains the:
A. Condenser
B. Evaporator
C. Compressor discharge line
D. Condenser and evaporator - Answer- Evaporator
A piece of ice weighs 20 Lbs and it's Pacific heat is 0.49. It will require_____Btu to heat
the piece of ice from 27°F to 31°F. - Answer- 31 - 27 = 4
4 x 20 = 80
80 x 0.49 = 39.2
39.2 BTUs
Of the following terms the largest amount in BTU for 1 pound of water is:
A. It's sensible heat
B. It's latent heat of fusion
C. It's latent heat of vaporization
, D. It's latent heat of melting - Answer- It's latent heat of vaporization
If the evaporator in a vapor compression cycle is not cold enough, it can be made colder
by:
A. Raising the evaporator pressure
B. Stopping the compressor temporarily
C. Lowering the evaporator pressure
D. Venting the refrigerant to the atmosphere - Answer- Lowering the evaporator
pressure
Calculate the amount of heat which will be absorbed when 15 pounds of solid
substance at a temperature of 30°F is changed to a liquid at 44°F - Answer-
The purpose of the condenser in the vapor compression cycle is to:
A. Save the refrigerant for reuse
B. Reduce the superheated vapor to evaporator temperature
C. Reduce the evaporator pressure
D. Lower the evaporator temperature - Answer- Save the refrigerant for re-use
In the vapor compression cycle, the compressor:
A. Heats the refrigerant vapor
B. Reduces evaporator pressure
C. Compresses the refrigerant vapor.
D. All of the above - Answer- Heats the refrigerant vapor
Reduces evaporator pressure
Compresses the refrigerant vapor.
Water can be made to boil at 50°F by:
A. Subcooling it to 50°F
B. Reducing the pressure to 14.7 psi absolute
C. Placing it under a high enough vacuum
D. Lowering the pressure to atmospheric pressure - Answer- Placing it under a high
enough vacuum
Chapter 3: Refrigerants - Answer-
An example of a halogen is:
A. Sulfur dioxide
B. Butane
C. Carbon dioxide
D. None of these - Answer- None of these
