Refrigeration cycle_________________?

Related Mcqs:

1. Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is_____________________?

   A. Positive
   B. Negative
   C. Zero
   D. Infinity

2. A refrigeration cycle is a reversed heat engine. Which of the following has the maximum value of the co-efficient of performance (COP) for a given refrigeration effect ?

   A. Vapor compression cycle using expansion valve
   B. Air refrigeration cycle
   C. Vapor compression cycle using expansion engine
   D. Carnot refrigeration cycle

3. What is the value of maximum COP in case of absorption refrigeration, if refrigeration provided is at temperature, TR (where, T1 and T2 are source & surrounding temperatures respectively.) ?

   A. TR/(T2 – TR) × (T1 – T2)/T1
   B. TR/(T2 – TR) × T1/(T1 – T2)
   C. TR/(T1 – TR) × (T1 – T2)/T1
   D. None of these

4. Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system ?

   A. Expansion valve
   B. Condenser
   C. Refrigerator
   D. Compressor

5. Air-refrigeration cycle________________?

   A. Is the most efficient of all refrigeration cycles
   B. Has very low efficiency
   C. Requires relatively large quantities of air to achieve a significant amount of refrigeration
   D. Both B. and C

6. Out of the following refrigeration cycles, which one has maximum COP ?

   A. Air cycle
   B. Carnot cycle
   C. Ordinary vapor compression cycle
   D. Vapor compression with a reversible expansion engine

7. In case of vapour compression refrigeration system, elevating the evaporator temperature (keeping the condenser temperature constant) results in_____________?

   A. Enhanced COP
   B. Decreased COP
   C. No change in the value of COP
   D. Increased or decreased COP; depending upon the type of refrigerant

8. Fundamental principle of refrigeration is based on the ______________ law of thermodynamics?

   A. Zeroth
   B. First
   C. Second
   D. Third

9. Which of the following has the minimum value of COP for a given refrigeration effect ?

   A. Reverse Carnot cycle
   B. Ordinary vapour-compression cycle
   C. Vapour-compression process with a reversible expansion engine
   D. Air refrigeration cycle

10. Lowering of condenser temperature (keeping the evaporator temperature constant) in case of vapour compression refrigeration system results in__________________?

    A. Increased COP
    B. Same COP
    C. Decreased COP
    D. Increased or decreased COP; depending upon the type of refrigerant