Refrigeration is usually measured in:

Refrigeration is usually measured in:

a. Kilojoules
b. Kilowatts
c. Tons
d. All the above






Answer: D

Superheat the evaporator is defined as:

Superheat the evaporator is defined as:

a. The most efficient way to remove heat from a process
b. The heat required to accelerate the cooling process
c. The additional heat absorbed by a refrigerant after it has vaporized
d. The best heat available






Answer: C

The heat that a refrigerant absorbs to cause it to change from a liquid state to a gaseous state is called:

The heat that a refrigerant absorbs to cause it to change from a liquid state to a gaseous state is called:

a. Sensible heat
b. Convection
c. Latent heat of E vaporization
d. Radiant heat





Answer: C

Natural refrigeration is best described by the example of an:

Natural refrigeration is best described by the example of an:

a. Cooling fan
b. Outdoor rink
c. Ice box
d. Ceiling fan






Answer: C

Which column in the refrigerant table lists the absolute pressure in kPa?

Which column in the refrigerant table lists the absolute pressure in kPa?

a) Column 1
b) Column 2
c) Column 3
d) Column 4
e) None of the above







Answer: B

If a cooled medium had an evaporation temperature of 2 degrees C, the evaporation temperature of the liquid refrigerant should be approximately

If a cooled medium had an evaporation temperature of 2 degrees C, the evaporation temperature of the liquid refrigerant should be approximately

a) 2 degrees C
b) 6 - 8 degrees C
c) 1 degree C
d) 0 degrees C
e) -8 to -3 degrees C







Answer: E

One tonne of refrigeration is

One tonne of refrigeration is

a) 13958 kJ per day
b) 100 kJ per minute
c) 233 kJ per minute
d) 13958 J per hour
e) 335 J per second






Answer: C

Refrigerant mediums will evaporate

Refrigerant mediums will evaporate

a) when pressure is increased
b) when temperature is increased
c) when they are diluted
d) when temperature is decreased
e) when heat is removed






Answer: B

The rate at which a system will remove heat from the refrigerated medium is defined as

The rate at which a system will remove heat from the refrigerated medium is defined as

a) coefficient of performance
b) net refrigerating effect
c) refrigeration capacity
d) compression ratio
e) differential efficiency






Answer: C

Which of the following statements about high-side pressure and temperature is true?

Which of the following statements about high-side pressure and temperature is true?

a) The heat flow is from the cooling medium to the hot refrigerant.
b) The condensing temperature of the vapour is 15 - 20 degrees C higher than the temperature of the medium used in the condenser.
c) The condensation temperature of the refrigerant will be lower if the pressure of the vapourized refrigerant is lowered.
d) The condenser functions by taking latent heat from the surrounding air and adding it as sensible heat to the refrigerant.
e) None of the above







Answer: B

Which of the following statements about low-side pressure and temperature is false?

Which of the following statements about low-side pressure and temperature is false?

a) The evaporation temperature of the refrigerant should be 5 - 10 degrees C higher than that of the cooled medium.
b) For a given amount of heat transfer an oversized evaporator can be operated at a higher temperature.
c) The low side pressure depends on the type of evaporation used.
d) The evaporation temperature of the refrigerant will be
higher if the evaporator lowers the refrigerant pressure.
e) All of the above.







Answer: A

The function of the condenser is to

The function of the condenser is to

a) vaporize the liquid refrigerant
b) change high pressure refrigerant vapour to liquid
c) pressurize low pressure refrigerant vapour
d) vent off vaporized refrigerant
e) lower the liquid refrigerant pressure





Answer: B

Which of the following is an example of a loss of latent heat? i) water evaporating ii) ice melting iii) refrigerant evaporating iv) air cooling

Which of the following is an example of a loss of latent heat?
i) water evaporating
ii) ice melting
iii) refrigerant evaporating
iv) air cooling

a) iv only
b) iii only
c) i, iii, and iv
d) both i and iii
e) none of the above

Answer: E

In the case of a simple ice box which of the following heat transfers is correct?

In the case of a simple ice box which of the following heat transfers is correct?

a) Air loses latent heat, ice does not gain any heat.
b) Air loses sensible heat, ice does not gain any heat.
c) Air loses sensible heat, ice gains sensible heat.
d) Air loses sensible heat, ice gains latent heat.
e) Air loses latent heat, ice gains latent heat.

Answer: D

The net refrigerating effect of a refrigerant is the amount of heat:

The net refrigerating effect of a refrigerant is the amount of heat:

a. Discharged by the condenser
b. Absorbed by the refrigerant in the evaporator
c. Absorbed by the refrigerant in the condenser
d. Discharged by the refrigerant in the evaporator
e. Absorbed by the evaporator





Answer: B

With regard to the condenser in a refrigeration system, which of the following statements is true?

With regard to the condenser in a refrigeration system, which of the following statements is true?

a. In the condenser, heat transfers from the cooling medium to the refrigerant
b. The condensing temperature of the refrigerant vapour is 15°-20°C higher than the temperature of the cooling medium
c. The condensing temperature of the refrigerant will be lower if the pressure of the refrigerant is increased
d. The condenser transfers latent heat from the cooling medium and adds it as sensible heat to the refrigerant
e. The refrigerant absorbs latent heat of condensation from the cooling medium.

Answer: B

When a liquid evaporates, it

When a liquid evaporates, it

a. Gains sensible heat
b. Gains latent heat
c. Loses sensible heat
d. Loses latent heat
e. Loses in heat content






Answer: B

One tonne of refrigeration is:

One tonne of refrigeration is:

a. 13 958 kJ per day
b. 1000 kg of mass
c. 233 kJ per minute
d. 13958 J per hour
e. 12000 BTU per hour







Answer: C

The function of the condenser in a refrigeration system is to:

The function of the condenser in a refrigeration system is to:

a. Lower the temperature of the liquid refrigerant
b. Change high pressure refrigerant vapour to liquid
c. Pressurize low pressure refrigerant vapour
d. Vent off vaporized refrigerant
e. Lower the liquid refrigerant pressure







Answer: B

Which of the following is an example of a loss of latent heat?

Which of the following is an example of a loss of latent heat?

a. Steam condenses
b. Water evaporates
c. Ice melts
d. Refrigerant evaporates
e. Air is cooled





Answer: A