In refrigerators, the temperature difference between the evaporating refrigerant and the medium being cooled should be_________________?

Related Mcqs:

1. The vapor pressure of refrigerant should be_________________?

   A. lower than atmospheric pressure
   B. higher than atmospheric pressure
   C. equal to atmospheric pressure
   D. could be anything
   E. none of the above

2. A refrigeration cycle operates between condenser temperature of + 27°C and evaporator temperature of- 23°C. The Cannot coefficient of performance of cycle will be_________________?

   A. 0.2
   B. 1.2
   C. 5
   D. 6
   E. 10

3. If a heat pump cycle operates between the condenser temperature of +27°C and evaporator temperature of – 23°C, then the Carnot COP will be_________________?

   A. 0.2
   B. 1.2
   C. 5
   D. 6
   E. 10

4. Most of the domestic refrigerators work on the following refrigeration system _________________?

   A. vapour compression
   B. vapour absorption
   C. carnot cycle
   D. electrolux refrigerator
   E. dual cycle

5. In refrigerator, liquid receiver is required between condenser and flow controlling device, if quantity of refrigerant for system is_____________________?

   A. less than 2 kg
   B. more than or equal to 3.65 kg
   C. more than 10 kg
   D. there is no such consideration
   E. pone of the above

6. For proper refrigeration in a cabinet, if the temperature and vapour pressure difference between cabinet and atmosphere is high, then_________________?

   A. bigger cabinet should be used
   B. smaller cabinet should be used
   C. perfectly tight vapour seal should be used
   D. refrigerant with lower evaporation temperature should be used
   E. refrigerant with high boiling point must be used

7. In vapor compression cycle, the condition of refrigerant is high pressure saturated liquid________________?

   A. after passing through the condenser
   B. before passing through the condenser
   C. after passing through the expansion or thiottle valve
   D. before entering the expansion valve
   E. before entering the compressor

8. The moisture in a refrigerant is removed by___________________?

   A. evaporator
   B. safety relief valve
   C. dehumidifier
   D. driers
   E. expansion valve

9. The coefficient of performance is the ratio of the refrigerant effect to the_________________?

   A. heat of compression
   B. work done by compressor
   C. enthalpy increase in compressor
   D. all of the above
   E. none of the above

10. One of the purposes of sub-cooling the liquid refrigerant is to________________?

    A. reduce compressor overheating
    B. reduce compressor discharge temperature
    C. increase cooling effect
    D. ensure that only liquid and not the vapour enters the expansion (throttling) valve
    E. none of the above