Nate core TESTS WITH ANSWERS A+ GRADE.
Propane and butane are ____ than air.
A. Same weight
B. Heavier
C. Lighter - B
Current in a closed circuit is limited by which of the following?
A. Heat
B. Voltage
C. Temperature
D. Resistance - D
_____ use two special helical rotors that introduce suction vapors then compress them.
A. All options are correct
B. Scroll compressors
C. Reciprocating compressors
D. Screw compressors - D
A high pressure steam boiler operates at a pressure greater than ____
A. 5 psig
B. 15 psig
C. 25 psig
D 20 psig - B
____ is the heat that is absorbed or extracted when a substance changes its state.
,A. Enthalpy
B. Entropy
C. Latent heat
D. Specific heat - C
Sight glass is present at _____ in the refrigeration cycle.
A. Liquid line
B. Evaporation line
C. Suction line
D. Expansion valve - A
When there is an increase in the heat load on the evaporator, the refrigerant will tend to evaporate at a
_____ rate.
A. Slower
B. Faster - B
The higher the ambient temperatures, ____ will be the evacuation time of the refrigerants from the
system.
A. Higher
B. Lesser - B
Which of the following shall not be used near flammable material.
A. Halide leak detector
B. Electronic leak detector
C. Ultrasonic leak detector
D. Sulfur leak detector - A
, The ____ of the manifold gauge set is used to charge, evacuate, add oil and recover refrigerant from a
refrigeration and air conditioning system.
A. Blue hose
B. Yellow hose
C. Red hose - B
____ is the temperature at which oil starts to produce a waxy substance that may interfere with the
refrigeration system.
A. Dash point
B. Boiling point
C. Flock point
D. Pour point - C
1 watt = ____ btu
A. 3140
B. 3.41
C. 0.341
D. 341 - B
Most of the heat transfer from the heat exchanger is by which of the following.
A. Convection
B. Evaporation
C. Radiation
D. Conduction - A
At 32°F, 1 lb of ice can be changed to 1 lb of water by adding _____ btu.
Propane and butane are ____ than air.
A. Same weight
B. Heavier
C. Lighter - B
Current in a closed circuit is limited by which of the following?
A. Heat
B. Voltage
C. Temperature
D. Resistance - D
_____ use two special helical rotors that introduce suction vapors then compress them.
A. All options are correct
B. Scroll compressors
C. Reciprocating compressors
D. Screw compressors - D
A high pressure steam boiler operates at a pressure greater than ____
A. 5 psig
B. 15 psig
C. 25 psig
D 20 psig - B
____ is the heat that is absorbed or extracted when a substance changes its state.
,A. Enthalpy
B. Entropy
C. Latent heat
D. Specific heat - C
Sight glass is present at _____ in the refrigeration cycle.
A. Liquid line
B. Evaporation line
C. Suction line
D. Expansion valve - A
When there is an increase in the heat load on the evaporator, the refrigerant will tend to evaporate at a
_____ rate.
A. Slower
B. Faster - B
The higher the ambient temperatures, ____ will be the evacuation time of the refrigerants from the
system.
A. Higher
B. Lesser - B
Which of the following shall not be used near flammable material.
A. Halide leak detector
B. Electronic leak detector
C. Ultrasonic leak detector
D. Sulfur leak detector - A
, The ____ of the manifold gauge set is used to charge, evacuate, add oil and recover refrigerant from a
refrigeration and air conditioning system.
A. Blue hose
B. Yellow hose
C. Red hose - B
____ is the temperature at which oil starts to produce a waxy substance that may interfere with the
refrigeration system.
A. Dash point
B. Boiling point
C. Flock point
D. Pour point - C
1 watt = ____ btu
A. 3140
B. 3.41
C. 0.341
D. 341 - B
Most of the heat transfer from the heat exchanger is by which of the following.
A. Convection
B. Evaporation
C. Radiation
D. Conduction - A
At 32°F, 1 lb of ice can be changed to 1 lb of water by adding _____ btu.
