Automobile Engineering Practice Set-4

Page 1 of 4

1. The compression ratio in petrol engine is kept less than in Diesel engine because

Less compression ratio gives better performance

It is just customary to have less compression ratio in petrol engines

It makes petrol engines lighter

Higher or equivalent compression ratio in petrol engines is not possible due to pre-ignition

2. Which of the following indicates multi-grade oil?

API 50

SAE 30

SAE20 W50

API SF

3. With the increase of battery temperature, the specific gravity of electrolyte

Decreases

Remains the same

Increases

None of these

4. The purpose of a balancer shaft is to

Increase inertia force of the rotating crankshaft

Balance the timing in the movement of the two groups of pistons

Reduce vibrations caused by the crankshaft rotation

Adjusts the timing of the intake and exhaust valve openings

5. The piston compression rings are made of

Cast iron

Aluminium

Bronze

Steel

6. In a forced feed lubrication system, the device used to guard against excessive oil pressure, is known as

Release chamber

Balancer

Stop valve

Relief valve

7. The main purpose of an engine's air cleaner is that it

Controls the engine's air intake volume

Reduces the engine's air intake noise

Prevents dust and other foreign matter from entering the engine

Prevents rain water from entering the engine

8. The caster is called positive when the top of the king pin is inclined to the

Rear of the vehicle

Left of the vehicle

Right of the vehicle

Front of the vehicle

9. The function of positive crankcase ventilation (PCV) system is that it

Feeds blow by gases to the exhaust manifold

Promotes combustion by creating a swirling movement in the air-fuel mixture

Returns blow by gases from the crankcase to the intake system

Mixes fuel with air

10. The compression ratio for Diesel engines usually lies in the range of

15-20

6-10

10-15

25-40

Page 2 of 4

11. The main function of a master cylinder is to

Boost the force applied to brake pedal

Adjust the extent of brake pedal free play

Convert brake pedal force into hydraulic pressure

Ensure that all the wheel brakes are supplied with the same amount of fluid pressure

12. The frequency of flashing of light per minute in a direction (side turn) indicator is about

9

9000

900

90

13. The reconditioning process used to give cylinder bore surfaces a crosshatch pattern, is known as

Shot peening

Boring

Porous plating

Honing

14. The natural gas is compressed in a CNG cylinder at a pressure of

200bar

250bar

220bar

300bar

15. The gradient resistance to a vehicle having a mass of 980 kg moving on an incline of 10° is

16.694 N

1669.4 N

1.6694 N

166.94 N

16. The function of a radiator fan in the cooling system is that

It cools the engine by blowing air onto the cylinder block

It draws heat out of the engine compartment

It blows air through the radiator when necessary

It is turned by wind force as the vehicle moves forward, and its rotation drives the water pump

17. In Spark Ignition Engine

(C) Both (A) and (B)

(B) The mixture of air and fuel is introduced into the cylinder from carburettor

(A) Only air is introduced into the cylinder

(D) None of these Correct Answer

18. The valve overlap in four stroke petrol engines is approximately

30°

60°

120°

90°

19. The heat transfer from coolant to air in the radiator of an automobile engine takes place by

Convection and radiation

Radiation only

Conduction, convection and radiation

Convention only

20. The aspect ratio (expressed in percentage) of the tyre is defined as the ratio of

Wheel diameter to section width

Section height to section width

Section width to section height

Wheel diameter to section height

Page 3 of 4

21. The basic purpose of a four wheel drive (4WD) system is that it

Delivers improved cornering on dry road surfaces

Eliminates the need of snow tyres, tyre chains, etc.

Ensures that effective braking can be performed, even on slippery surfaces

Ensures effective transmission of engine torque to all four wheels, even on slippery road surfaces

22. The exhaust gas from petrol engine contains

Petrol vapours

Carbon monoxide

Water vapours

All of these

23. In order to implement gear changes in the gear unit of an automatic transmission, a ___________ is used.

Hydraulic multi plate clutch

Magnetic clutch

Synchronizer

Planetary gear

24. The self ignition temperature of Diesel as compared to petrol is

Higher

Lower

Same

Depends on fuel quality

25. The basic characteristics of a brake fluid is

All of these

Low viscosity

Compatibility with rubber and metal parts

A high boiling point

26. The ignition coil is used to

Step down current

Step up current

Step up voltage

Step down voltage

27. The firing order for an opposed four cylinder l.C. engine is

1-3-4-2

1-4-3-2

1-2-3-4

1-3-2-4

28. The service brakes employed in cars are generally operated

Hydraulically

Pneumatically

None of these

Mechanically

29. The discharged lead acid battery has on its plates

Lead peroxide (PbO₂)

Sulphuric acid (H₂SO₄)

Spongy lead (Pb)

Lead sulphate (PbSO₄)

30. The two kinds of piston rings are

Compression and oil control rings

Compression and sliding seal rings

Pressure and sealing rings

Oil scrapper and oil control rings

Page 4 of 4

31. The purpose of a thermostat in an engine cooling system is to

Prevent the coolant from boiling

Indicate the coolant temperature

Pressurise the system to raise the boiling point

Allow the engine to warm up quickly

32. The purpose of turning radius gauges is to measure the

Difference in the toe angles of the left and right wheels

Free plays of the steering wheel

Turning radius of the left and right wheels

Contact areas of the tyres

33. The process of supplying the intake air to the engine cylinder at a pressure greater than the pressure of the surrounding atmosphere is known as

Detonation

Supercharging

Scavenging

Auto ignition

34. The process of removing the burnt gases from the engine cylinder by the fresh charge coming into the engine cylinder from the crankcase, is known as

Scavenging

Detonation

Priming

Cleaning

35. The main task of a battery in automobiles is to

Supply a large amount of power to turn the starter motor when the engine is being started

Supply electricity to the vehicle's electrical system at all times while the engine is running

Act as a reservoir or stabilizer of electricity

Supply electricity to the alternator

36. In aluminium cylinder blocks, the cylinder liners are made of

Brass

Ceramic

Aluminium

Cast iron

37. Free pedal play in car clutches is about

15 mm

60 mm

40 mm

25 mm

38. The sequence in which the force is transmitted through a brake system when the brake pedal is depressed is

Brake pedal, vacuum servo mechanism, master cylinder, brake lines, brake pads

Brake pedal, master cylinder, vacuum servo mechanism, brake lines, brake pads

Brake pedal, brake lines, vacuum servo mechanism, master cylinder, brake pads

Brake pedal, master cylinder, brake lines, vacuum servo mechanism, brake pads

39. The boiling point of Diesel fuel is in the range of

120°C to 180°C

180°C to 360 °C

100°C to 120°C

70°C to 100°C

40. The device for smoothening out the power impulses from the engine is called

Torque converter

Clutch

Flywheel

Differential

Automobile Engineering Practice Set-4

Related

Leave a ReplyCancel reply

Secured Payments

Protection

Automobile Engineering Practice Set-4

Share this Now with Friends:

Related

Leave a ReplyCancel reply

Secured Payments

Protection