Internal Combustion (IC) Engine MCQ
Internal Combustion (IC) Engine MCQ, IC Engine MCQ, Internal Combustion Engine MCQ, Basic Mechanical Engineering MCQ, BME MCQ, GATE objective questions, Objective Questions on Internal Combustion (IC) Engine, Engineering MCQ
Multiple Choice Questions
Q.1. In a four stroke cycle engine; the four operations namely suction, compression, expansion and exhaust are completed in the number of revolutions of crank shaft equal to
- Four
- Three
- Two
- One
Answer: Two
Q.2. In a two stroke cycle engine, the operations namely suction, compression, expansion and exhaust are completed in the number of revolutions of crank shaft equal to
- Four
- Three
- Two
- One
Answer: One
Q.3. The following is an S.I. engine:
- Diesel Engine
- Petrol Engine
- Gas Engine
- None of the above
Answer: Petrol Engine
Q.4. The following is a C.I. engine
- Diesel Engine
- Petrol Engine
- Gas Engine
- None of the above
Answer: Diesel Engine
Q.5. In a four stroke cycle petrol engine, during suction stroke
- only air is sucked in
- only fuel is sucked in
- mixture of fuel and air is sucked in
- None of the above
Answer: mixture of fuel and air is sucked in
Q.6. In four stroke cycle diesel engine, during suction stroke
- only air is sucked in
- only fuel is sucked in
- mixture of fuel and air is sucked in
- None of the above
Answer: only air is sucked in
Q.7. The two stroke cycle engine has
- one suction valve and one exhaust valve operated by one cam
- one suction valve and one exhaust valve operated by two cams
- one port covered and uncovered by piston to effect charging and exhausting
- None of the above
Answer: one port covered and uncovered by piston to effect charging and exhausting
Q.8. For same output, same speed and same compression ratio the thermal efficiency of a two stroke cycle petrol engine as compared to that for four stroke cycle petrol engine is
- More
- Less
- Same as long as compression ratio is same
- Same as long as output is same
Answer: Less
Q.9. The ratio of brake power to indicated power of an I.C. Engine is called
- Mechanical efficiency
- Thermal efficiency
- Volumetric efficiency
- Relative efficiency
Answer: Mechanical efficiency
Q.10. The thermal efficiency of petrol engine as compared to diesel engine is
- Lower
- Higher
- Same for same output
- Same for same speed
Answer: Lower
Q.11. Compression ratio of petrol engines is in the range of
- 2 to 3
- 7 to 10
- 16 to 20
- None of the above
Answer: 7 to 10
Q.12. Compression ratio of diesel engines may have a range
- 8 to 10
- 10 to 15
- 16 to 20
- None of the above
Answer: 16 to 20
Q.13. The thermal efficiency of a good I.C. Engine at the rated load is in the range of
- 80 to 0%
- 60 to 70%
- 30 to 35%
- 10 to 20%
Answer: 30 to 35%
Q.14. In case of S.I. Engine, to have best thermal efficiency the fuel air mixture ratio should be
- Lean
- Rich
- May be lean or rich
- Chemically correct
Answer: Chemically correct
Q.15. The fuel air ratio for maximum power of S.I. engines, should be
- Lean
- Rich
- May be rich or lean
- Chemically correct
Answer: Chemically correct
Q.16. Carburettor is used for
- S.I. Engines
- Gas Engines
- C.I. Engines
- None of the above
Answer: S.I. Engines
Q.17. Fuel injector is used in
- S.I. Engines
- Gas Engines
- C.I. Engines
- None of the above
Answer: C.I. Engines
Q.18. In S.I. Engine, to develop high voltage for spark plug
- Battery is installed
- Distributor is installed
- Carburettor is installed
- Ignition coil is installed
Answer: Ignition coil is installed
Q.19. Which is a false statement in the context of the parts of an IC engine ?
- the piston is connected to the small end of connecting rod by a gudgeon pin
- crank pin connects the big end of connecting rod to crank arm
- the reciprocating motion of the piston is converted to the rotary motion by the connecting rod and crank mechanism
- the crankshaft provides the power and direction to the suction and exhaust valves
Answer: the crankshaft provides the power and direction to the suction and exhaust valves
Q.20. What is the main shaft of an engine that controls the movement of piston?
- axle
- drive shaft
- crankshaft
- camshaft
Answer: crankshaft
Q.21. What is mounted on the crankshaft to transform rotary motion into back-and-forth motion for actuating the valves?
- crank
- crank and slider
- camshaft
- flywheel
Answer: camshaft
Q.22. In four stroke engines, the camshaft is connected to the crankshaft by gears or chain and rotates at
- half the crankshaft speed
- three-fourth the crankshaft speed
- equal the crankshaft speed
- double the crankshaft speed
Answer: half the crankshaft speed
Q.23. The slotted grooves on oil rings for pistons help to
- seal the cylinder
- minimise friction
- prevent the piston from wear
- provide an escape for the oil that the slots edge out from the cylinder walls
Answer: provide an escape for the oil that the slots edge out from the cylinder walls
Q.24. The number of working strokes per minute in case of four stroke IC engine will be equal to
- N/2
- N
- 2N
- 4N
where N is represents the revolutions turned by the crankshaft in one minute.
Answer: N/2
Q.25. For the same compression ratio and heat supplied, the air standard efficiency of an Otto cycle compared to that of a Diesel cycle is
- less
- more
- equal
- unpredictable
Answer: equal
Q.26. Which is not the common component between a petrol and a diesel engine?
- camshaft
- exhaust silencer
- spray nozzle
- dynamo
Answer: spray nozzle
Q.27. Which is not a part of petrol engine?
- valve mechanism
- fuel injector
- induction coil
- air filter
Answer: induction coil
Q.28. Which is the correct statement in the context of two-stroke engines?
- compression ratio is always lower than that of a four stroke cycle engine
- there is only one valve for inlet and exhaust
- charge enters the engine cylinder, through ports only
- a Diesel engine cannot operate on two stroke cycle
Answer: there is only one valve for inlet and exhaust
Q.29. Compared to four-stroke cycle engine, a two-stroke cycle engine
- can be easily started
- has lesser shocks and vibrations
- has lower fuel consumption
- is smaller in size for-the same output
Answer: can be easily started
Q.30. Which aspect is not true for a two-stroke cycle engine when compared with a four stroke cycle engine?
- cycle is completed in one stroke of the piston
- uniform turning moment and hence a lighter flywheel
- theoretically develops twice the power
- noisy exhaust
- more consumption of lubricating oil
Answer: cycle is completed in one stroke of the piston