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.

The change in evaporator temperature in a refrigeration cycle, as compared to change in condenser temperature, influences the value of C.O.P_____________________?
A more
B less
C equally.
D unpredictable
Correct Answer: more
Which of the following refrigerants has lowest freezing point_______________?
A Freon-12
B NH3
C C02
D Freon-22
Correct Answer: Freon-22
The refrigeration effect in a dry evaporator compared to flooded evaporator in a similar plant is_________________?
A same
B more
C less
D more or less depending on ambient conditions
Correct Answer: less
Most of the domestic refrigerators work on the following refrigeration system _________________?
A vapour compression
B vapour absorption
C carnot cycle
D electrolux refrigerator
Correct Answer: vapour compression
The C.O.P of a refrigeration cycle with increase in evaporator temperature, keeping condenser temperature constant, will______________________?
A increase
B decrease
C remain unaffected
D may increase or decrease depending on the type of refrigerant used
Correct Answer: increase
For obtaining high COP, the pressure range of compressor should be_______________?
A high
B low
C optimum
D any value
Correct Answer: low
Super heating in a refrigeration cycle __________________?
A increases COP
B decreases COP
C COP remains unaltered
D other factors decide COP
Correct Answer: decreases COP
Moisture in freon refrigeration system causes________________?
A ineffective refrigeration
B high power consumption
C freezing automatic regulating valve
D corrosion of whole system
Correct Answer: freezing automatic regulating valve
The leaks in a refrigeration system using Freon are detected by____________________?
A halide torch which on detection produces greenish flame lighting
B sulphur sticks which on detection gives white smoke
C using reagents
D smelling
Correct Answer: halide torch which on detection produces greenish flame lighting
In vapour compression cycle using NH3 as refrigerant, initial charge is filled at_________________?
A suction of compressor
B delivery of compressor
C high pressure side close to receiver
D low pressure side near receiver
Correct Answer: high pressure side close to receiver