Objective Questions on Mechanical Engineering

73-In a shell and coil condenser:

(A) Water flows in the shell and refrigerant in the coil

(B) Only refrigerant flows through the shell as well as coil

(C) Only water flows through the shell as well as coil

(D) Water flows in the coil and refrigerant in the shell


74-In an air conditioning system, the comfort conditions are defined by:

(A) 15°C DBT 90% RH

(B) 25°C DBT 35% RH

(C) 20°C DBT 80% RH

(D) 22°C DBT 60% RH


75-The electrical component of automobile air conditioner allows to engage and disengage the compressor from the thermostat:

(A) Rheostat

(B) Thermostat

(C) Fuse

(D) Magnetic clutch


76-The swash plate compressor is most frequently used in:

(A) Refrigerators

(B) Window air conditioners

(C) Split air conditioners

(D) Car air conditioners


77-Which of the following refrigerant has the lowest freezing point?

(A) Ammonia

(B) Freon-11

(C) Freon-22

(D) Freon-12


78-The component common for vapour compression and vapour absorption system is:

(A) Rectifier

(B) Condenser

(C) Generator

(D) Absorber


79-Modification of R12 to R134A refrigerant is called:

(A) Recharging

(B) Recovery

(C) Retrofit

(D) None of the above


80-Which one of the following oxy fuel gas flame has the highest flame temperature?

(A) Oxy hydrogen

(B) Oxy acetylene flame

(C) Oxy coal gas flame

(D) Oxy LPG flame


81-The forging of steel is done at a temperature of:

(A) 400°C

(B) 800°C

(C) 1100°C

(D) 1500°C


82-The electric resistance welding operates with:

(A) Low current and high voltage

(B) High current and low voltage

(C) Low current and low voltage

(D) High current and high voltage


83-Spot welding, projection welding and seam welding belong to the category of:

(A) Arc welding

(B) Thermit welding

(C) Forge welding

(D) Resistance welding


84-Which one of the following is not a fusion welding process?

(A) Gas welding

(B) Arc welding

(C) Resistance welding

(D) Brazing



73-(D), 74-(D), 75-(D), 76-(D), 77-(C), 78-(B), 79-(C), 80-(C), 81-(C), 82-(B), 83-(D), 84-(D)