A. Increased COP
B. Same COP
C. Decreased COP
D. Increased or decreased COP; depending upon the type of refrigerant
Related Mcqs:
- 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 - The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is__________________?
A. Less pronounced
B. More pronounced
C. Equal
D. Data insufficient, can’t be predicted - In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be________________?
A. 5.2
B. 6.2
C. 0.168
D. Data insufficient, can’t be found out - 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 - 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 - Which of the following is a widely used refrigerant in vapour compression refrigeration system (using large centrifugal compressor) ?
A. Freon
B. Liquid sulphur dioxide
C. Methyl chloride
D. Ammonia - The vapour pressure of water is given by, in Psat = A – (5000/T), where A is a constant, Psat is the vapour pressure in atm. and T is the temperature in K. The vapor pressure of water in atm. at 50°C is approximately__________________?
A. 0.07
B. 0.09
C. 0.11
D. 0.13 - Vapour which is at a pressure smaller than the saturation pressure for the temperature involved is called a _____________ vapour?
A. Superheated
B. Desuperheated
C. Non-condensable
D. None of these - 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 - 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
