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41.

In vapour compression cycle the highest temperature of the refrigerant during the cycle occurs

A.	After expansion valve	B.	After evaporator
C.	After condenser	D.	After compression
E.	None of the above

42.

During compression in a vapour compression cycle of the refrigerant is super heated

A.	C.O.P. is reduced	B.	C.O.P. is increased
C.	Work done is reduced	D.	Refrigerating effect is reduced
E.	None of the above

43.

Dry bulb temperature depends on

A.	Humidity of air	B.	Water vapour content of air
C.	Condition of air	D.	All above
E.	None of the above

44.

The heat removed capacity of a one ton refrigerator is

A.	100 kcal/4 hour	B.	100 kcal/hour
C.	50 kcal/min	D.	25 kcal/sec
E.	None of the above

45.

A refrigerating system operates on the reversed Carnot cycle. The higher temperature of the refrigerant in the system is 40?C and the lower is - 15?C. The capacity is to be 10 tons. Neglecting all losses, the coefficient of performance of the system would be

A.	2.67	B.	3.75
C.	4.69	D.	7.36
E.	9.41

46.

No refrigerator using reversed Carnot cycle has been constructed because

A.	It is less efficient	B.	It requires bulky machines
C.	It is uneconomical	D.	Isentropic portions of cycle require low speeds whereas isothermal protuons require high speeds

47.

In a domestic refrigerator if the compressor runs continuously, it shows that

A.	The system is working perfectly all right	B.	The refrigeration is to full capacity
C.	The system is overloaded	D.	Any of the above
E.	None of the above

48.

If the compressor of a refrigeration system is noisy, it shows that

A.	Compressor drive coupling is loose	B.	Lack of oil
C.	Internal parts of compressor broken	D.	Compressor or motor loose on base
E.	Any of the above

49.

If a discharge pressure of a refrigeration compressor is too high, it shows there is (are)

A.	Too little or too warm condenser water	B.	Fouled tubes in shell and tube condenser
C.	Improper operations of evaporator condenser	D.	Overcharge of refrigerant
E.	Any of the above

50.

If the discharge pressure of a refrigeration compressor is too high it shows

A.	Too little or to warm condenser water	B.	Lack of refrigerant
C.	Excessive cooling load	D.	Lack of compressor lubrication
E.	Any of the above