M C Q s D r i v e

Mechanical Engineering Mcqs 1919 MCQs [All-Courses]

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Mechanical Engineering MCQs prepared for job test and interview preparation, especially for fresh graduates, students, and candidates appearing in competitive exams. These multiple-choice questions cover key topics such as Machine Design, Theory of Machines, Hydraulic Machines, and other important mechanical engineering concepts.

Freon group of refrigerants are___________________?

A inflammable
B
C non-inflammable and toxic
D non-toxic and inflammable
Correct Answer: inflammable

The lower horizontal line of the refrigeration cycle plotted on pressure-enthalpy-diagram represents_____________________?

A condensation of the refrigerant vapour
B evaporation of the refrigerant liquid
C compression of the refrigerant vapour
D metering of the refrigerant liquid
Correct Answer: evaporation of the refrigerant liquid

In a refrigeration cycle, the flow of refrigerant is controlled by___________________?

A compressor
B condenser
C evaporator
D expansion valve
Correct Answer: expansion valve

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
Correct Answer: 6

Aqua ammonia is used as refrigerant in the following type of refrigeration system_________________?

A compression
B direct
C indirect
D absorption
Correct Answer: absorption

Efficiency of a Carnot engine is given as 80%. If the- cycle direction be reversed, what will be the value of COP of reversed Carnot cycle_________________?

A 1.25
B 0.8
C 0.5
D 0.25
Correct Answer: 0.25

In vapor compression refrigeration system, refrigerant occurs as liquid between_________________?

A condenser and expansion valve
B compressor and evaporator
C expansion valve and evaporator
D compressor and condenser
Correct Answer: expansion valve and evaporator

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
Correct Answer: 5

Accumulators should have adequate volume to store refrigerant charge at least_________________?

A 10%
B 25%
C 50%
D 75%
Correct Answer: 50%

In a flooded evaporator refrigerator, an accumulator at suction of compressor is used to___________________?

A collect liquid refrigerant and prevent it from going to compressor
B detect liquid in vapour
C superheat the vapour
D collect vapours
Correct Answer: collect liquid refrigerant and prevent it from going to compressor