Automobile Engineering 1000+ MCQ with answer for NMAT

1. The function of positive crankcase ventilation (PCV) system is that it
A. Mixes fuel with air
B. Promotes combustion by creating a swirling movement in the air-fuel mixture
C. Returns blow by gases from the crankcase to the intake system
D. Feeds blow by gases to the exhaust manifold
Answer : C

2. The main function of intake manifold is that it
A. Promotes the mixture of air and fuel
B. Reduces intake noise
C. Cools the intake air to a suitable temperature
D. Distributes intake air equally to the cylinders
Answer : D

3. The most effective method of controlling S.I. engine exhaust emission is by
A. Recirculating exhaust
B. Using catalytic converter
C. Using some additives in the fuel
D. None of these
Answer : B

4. In a four wheel drive (4WD), the numbers of gear boxes are
A. 1
B. 2
C. 3
D. 4
Answer : B

5. The number of exhaust manifolds in a V6 engine is
A. One
B. Two
C. Four
D. Eight
Answer : B

6. In which of the following conditions, the idle CO percentage should be measured with the vehicle?
A. Headlights and other electrical devices are switched off
B. Headlights and other electrical devices are switched on
C. Headlights and other lights are switched off
D. Headlights are switched on
Answer : A

7. With the increase of battery temperature, the specific gravity of electrolyte
A. Increases
B. Decreases
C. Remains the same
D. None of these
Answer : B

8. The octane rating of petrol commercially available is
A. 85-95
B. 95-100
C. 100-110
D. 110-125
Answer : A

9. The temperature at which tyre inflation pressure should be checked is
A. 20°C
B. 25°C
C. 35°C
D. Ambient temperature
Answer : D

10. The mechanical efficiency (?m) of an I.C. engine is equal to (where I.P. = Indicated power, B.P. = Brake power and F.P. = Frictional power)
A. I.P/B.P.
B. B.P/I.P.
C. B.P/F.P.
D. F.P/B.P.
Answer : B

11. The timing belt is attached to the camshaft pulley and
A. Timing belt drive pulley
B. Distributor
C. Radiator fan pulley
D. Alternator pulley
Answer : A

12. The most commonly used power plant in automobiles is
A. Gas turbine
B. I.C. engine
C. Battery
D. None of these
Answer : B

13. The connecting rod connects the piston and the
A. Cylinder head
B. Cylinder block
C. Camshaft
D. Crankshaft
Answer : D

14. The connecting rod is attached to the piston by the
A. Cap bolt
B. Piston pin
C. Cap roller bearing
D. Rod cap
Answer : B

15. In order to implement gear changes in the gear unit of an automatic transmission, a ________ is used.
A. Synchronizer
B. Planetary gear
C. Magnetic clutch
D. Hydraulic multi plate clutch
Answer : D

16. The ignition coil is used to
A. Step up current
B. Step down current
C. Step up voltage
D. Step down voltage
Answer : C

17. Bead wires are made of
A. Steel
B. Copper
C. Zinc
D. Aluminium
Answer : A

18. The main purpose of an engine's air cleaner is that it
A. Controls the engine's air intake volume
B. Reduces the engine's air intake noise
C. Prevents rain water from entering the engine
D. Prevents dust and other foreign matter from entering the engine
Answer : D

19. The temperature indicating instrument in vehicles indicates the temperature of
A. Engine piston
B. Engine cylinder
C. Lubricating oil
D. Jacket cooling water
Answer : D

20. The effect of having excess camber is
A. Excessive steering alignment torque
B. Hard steering
C. Too much traction
D. Uneven tyre wear
Answer : D

21. The auto ignition in a spark ignition engine means
A. Automatic ignition of the charge at the end of compression
B. Ignition induced by the passage of a spark
C. Ignition of the charge before the passage of flame front
D. Ignition induced to supplement the process of normal combustion
Answer : C

22. The effect of vapour locking on the brake performance is that the
A. Brakes function more effectively
B. Brakes fail completely
C. Brake operation is delayed after depression of the brake pedal
D. Vapour locking has no effect on brake performance
Answer : B

23. The tilting of the front wheels away from the vertical, when viewed from the front of the car, is called
A. Camber
B. Caster
C. Toe in
D. Toe out
Answer : A

24. The coefficient of rolling resistance for a truck weighing 63,500 N is 0.018. The rolling resistance to the truck is
A. 1.143 N
B. 11.43 N
C. 114.3 N
D. 1143 N
Answer : D

25. For the same maximum pressure and temperature
A. Diesel cycle is more efficient than Otto cycle
B. Otto cycle is more efficient than Diesel cycle
C. Both Otto cycle and Diesel cycle are equally efficient
D. None of the above
Answer : A

26. The component in the radiator of an automobile that increases the boiling point of water is
A. Drain plug
B. Water jacket
C. Vacuum valve
D. Pressure cap
Answer : D

27. The clutch is located between the transmission and the
A. Engine
B. Rear axle
C. Propeller shaft
D. Differential
Answer : A

28. In aluminium cylinder blocks, the cylinder liners are made of
A. Aluminium
B. Ceramic
C. Brass
D. Cast iron
Answer : D

29. In Diesel engines, the duration between the time of injection and the time of ignition is called
A. Spill cut-off
B. Delay period
C. Injection period
D. Ignition period
Answer : B

30. The air resistance to a car at 20 kmph is R. The air resistance at 40 kmph will be
A. R
B. 2 R
C. 4R
D. 4 R²
Answer : C

31. In a four cylinder inline engine, the number of firing strokes in one revolution of the crank is
A. 1
B. 2
C. 3
D. 4
Answer : B

32. The function of oil control rings is that it
A. Lubricates the cylinder wall by releasing oil from its hole
B. Keeps the cylinder wall lubricated by holding oil in its channel
C. Prevents engine oil from going into the combustion chamber and returns excess lubricating oil off the cylinder wall through the return holes in the piston to the oil pan
D. Maintains a seal and prevents escape of burned gases and oil leakage
Answer : C

33. In automobiles G.V.W. refers to
A. Gross vehicle width
B. Gross vehicle weight
C. Gross vehicle wheel base
D. Gross vehicle wheel track
Answer : B

34. The fuel pump in the programmed fuel injection (PFI) system is located
A. Between the fuel filler pipe and fuel tank
B. In the fuel tank
C. On the distributor mounting in the engine compartment
D. On the engine compartment bulkhead
Answer : B

35. The lubrication oil flow in an engine is in the order as
A. Oil strainer, oil pump, relief valve, oil filter, cylinder block, cylinder head and oil pan
B. Oil pump, oil strainer, relief valve, oil filter, cylinder block, cylinder head and oil pan
C. Oil strainer, oil filter, relief valve, oil pump, cylinder block, cylinder head and oil pan
D. Oil strainer, oil pump, relief valve, oil filter, cylinder head, cylinder block and oil pan
Answer : A

36. The cam shaft in an engine is always mounted
A. Parallel to the crankshaft
B. Perpendicular to the crankshaft
C. Inclined to the crankshaft
D. None of these
Answer : A

37. The starter motor is driven by
A. Chain drive
B. Gear drive
C. Flat belt drive
D. V-belt drive
Answer : B

38. The gear shift lever requires two separate motions to shift gears, and the first movement
A. Moves the synchronizer
B. Selects the synchronizer
C. Meshes the gears
D. Operates the clutch
Answer : B

39. In bias ply tyres
A. All plies run parallel to one another
B. Belts of steel mesh are used in the tyres
C. One ply layer runs diagonally one way and another layer runs diagonally the other way
D. All of the above
Answer : C

40. The connecting rods are generally made of ________ shaped crosssection.
A. I
B. C
C. L
D. H
Answer : A

41. When a gear box has four forward speeds and one reverse speed, it is said to be a
A. 3-speed gear box
B. 4-speed gear box
C. 5-speed gear box
D. 6-speed gear box
Answer : B

42. In case of a Diesel car, the pressure at the end of compression is of the order of
A. 15 bar
B. 25 bar
C. 35 bar
D. 45 bar
Answer : D

43. The brake warning light warns the driver of
A. Water in the master cylinder
B. Air in the hydraulic system
C. Failure of the primary or secondary circuit of hydraulic system
D. Power brake failure
Answer : C

44. The power actually developed inside the engine cylinder is called as
A. Indicated power
B. Brake power
C. Frictional power
D. None of these
Answer : A

45. In a Diesel engine, the function of a fuel injector is to
A. Mix the fuel and air
B. Ignite the air-fuel mixture
C. Provide flame front for ignition
D. Spray atomized fuel in the cylinder
Answer : D

46. In an engine, the temperature of the piston will be more at the
A. Crown of the piston
B. Skirt of the piston
C. Piston walls
D. Piston rings
Answer : A

47. Incorrect steering axis inclination (S.A.I.) causes
A. Tendency to assume toe-out orientation
B. Generation of a braking effect at tight corners
C. Poor recovery of the steering wheel after making a turn
D. The vehicle to pull to the side of lesser inclination
Answer : C

48. The negative terminal post on the top of a battery is
A. Smaller than the positive terminal post
B. Larger than the positive terminal post
C. Of the same size as the positive terminal post
D. None of these
Answer : A

49. Thinner is added to the paint in order to
A. Make pigments and resin mix easily
B. Make paint film hard
C. Optimise its viscosity
D. None of these
Answer : C

50. The frequency of flashing of light per minute in a direction (side turn) indicator is about
A. 9
B. 90
C. 900
D. 9000
Answer : B