A. +ve
B. -ve
C. 0
D. Either of the above three; depends on the nature of refrigerant
Related Mcqs:
- 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 - Ideal refrigeration cycle is____________________?
A. Same as Carnot cycle
B. Same as reverse Carnot cycle
C. Dependent on the refrigerant’s properties
D. The least efficient of all refrigeration processes - The internal energy of an ideal gas does not change in a reversible _____________ process?
A. Isothermal
B. Adiabatic
C. Isobaric
D. Isometric - A refrigeration cycle is the same as a _____________ cycle?
A. Turbine
B. Heat engine
C. Reversed heat engine
D. None of these - Internal energy change of a system over one complete cycle in a cyclic process is__________________?
A. Zero
B. +ve
C. -ve
D. Dependent on the path - A car tyre of volume 0.057 m3 is inflated to 300 kPa at 300 K. After the car is driven for 10 hours, the pressure in the tyre increases to 330 kPa. Assume air is an ideal gas and Cv for air is 21 J/mole.K. The change in the internal energy of air in the tyre in J/mole is__________________?
A. 380
B. 630
C. 760
D. 880 - 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 - An ideal gas is taken around the cycle ABCA as shown in P-V diagram below: The work done by the gas during the cycle is equal to_________________?
A. 12 P1V1
B. 6 P1 V1
C. 3 P1V1
D. P1 V1
