Objective questions in Mechanical Engineering
(A) 0.1 kN per square meter
(B) 1.0 kN per square meter
(C) 10 kN per square meter
(D) 100 kN per square meter
(A) Horizontal position
(B) Vertical position
(C) Inclined
(D) At any orientation
(A) Zero
(B) Minimum
(C) Maximum
(D) Positive4. 1 kgf/cm2 is equal to
(A) 1 mm Hg
(B) 100 mm Hg
(C) 735.6 mm Hg
(D) 760 mm Hg5. For a reversible adiabatic process, the change in entropy of the system and surroundings is
(A) Unity
(B) Zero
(C) Infinite
(D) Positive
6. During the throttling process
(A) Internal energy does not change
(B) Pressure does not change
(C) Entropy does not change
(D) Enthalpy does not change
7. The cycle generally used for gas turbines is
(A) Rankine cycle
(B) Brayton cycle
(C) Dual cycle
(D) Carnot cycle
8. At the critical point, the enthalpy of vaporization is
(A) Only dependent on temperature
(B) Zero
(C) Minimum
(D) Maximum
9. The process during which external work is done is not zero,
(A) Constant volume process
(B) Constant pressure process
(C) Throttling
(D) Free Expansion
10. The efficiency of a diesel cycle will be maximum when
(A) Speed is high
(B) Injection pressure is high
(C) Cylinder is water-cooled
(D) Cut off is zero
11. A reversible engine working between temperature limits of 500 K and 1000 K received 50 kJ of heat. The work done by the engine will be
(A) 50 kJ
(B) 25 kJ
(C) -25 kJ
(D) 100 kJ
12. The function of a condenser in a steam power plant is
(A) to reduce back pressure
(B) to utilize the heat of exhaust steam
(C) to preheat feed water with exhaust steam
(D) to act as a heat sink
13. 1 Torr is equal to
(A) 1 mm Hg
(B) 13.6 cm of water column
(C) 760 mm of Hg
(D) 760 mm of Water
14. The negative loop in the PV diagrams of a petrol engine is due to
(A) Pre-ignition
(B) Detonation
(C) Suction of air
(D) Early opening of the exhaust valve
15. In the case of a white body, absorptivity is
(A) Zero
(B) Between 0 and 0.5
(C) More than 0.5
(D) 1
16. Solar cells are made of
(A) Steel
(B) Silica
(C) Antimony
(D) Phosphorus
17. A newly charged ammonia compression system, the clicking sound in the expansion valve indicates
(A) Evaporator coils chocked
(B) Excessive ammonia charged
(C) High pressure after compression
(D) Lack of ammonia
18. In a vapor absorption system the function of the rectifier is
(A) To separate ammonia and water
(B) To cool the vapor leaving the analyzer
(C) To dissolve ammonia in water
(D) To add energy from an external source
19. During air conditioning, whenever two or more streams of moist are mixed, they follow
(A) Adiabatic process
(B) Isothermal process
(C) Polytropic process
(D) Isobaric process
20. In a cooling tower, heat is dissipated mainly by
(A) Radiation
(B) Conduction
(C) Convection
(D) Evaporation
Answers to these objective questions:
1-C, 2-B, 3-A, 4-C, 5-B, 6-D, 7-B, 8-B, 9-B, 10-D, 11-B, 12-D, 13-A, 14-A, 15-A, 16-B, 17-C, 18-A, 19-A, 20-D
These objective questions help you to have an idea of what kind of thermal engineering questions can be asked in any competitive exam like GATE 2024 or interview related to mechanical engineering.