Explore topic-wise MCQs in Testing Subject.

This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.

1.

In a scooter engine the cylinder is lubricated by

A. Cylinder does not require lubrication
B. Lubrication plug
C. Pressure lubrication
D. Splash lubrication
E. Mixing lubricating oil in the fuel
Answer» F.
Discussion
2.

The maximum pressure generated by the fuel injection pump does not reach the nozzle end immediately. The lag is due to

A. friction in the oil column
B. pressure wave in the oil column
C. turbulence in the cylinder
D. none of the above
E. None of the above
Answer» C. turbulence in the cylinder
Discussion
3.

Diesel engines are also known as

A. S.I. engines
B. C.I. engines
C. Steam engines
D. none of the above
E. None of the above
Answer» C. Steam engines
Discussion
4.

The problem of exhaust emissions can be handled by

A. engine design modification
B. treatment of exhaust gases
C. fuel modification
D. All of the above
E. None of the above
Answer» E. None of the above
Discussion
5.

For balancing single cylinder engine a counter weight is added to

A. Crankshaft
B. Piston rings
C. Piston
D. Gudgeon pin
E. Connecting rod
Answer» B. Piston rings
Discussion
6.

A smoky blue exhaust is due to

A. Burning of oil in combustion chamber
B. Incorrect valve adjustment
C. Excessive air
D. Incorrect tappet adjustment
E. Excessive rich mixture
Answer» B. Incorrect valve adjustment
Discussion
7.

In an engine shows lack of power on running the probable cause could be

A. Poor compression
B. Faulty ignition
C. Overheating
D. Over cooling
E. Any of the above
Answer» F.
Discussion
8.

High sulphur content of petrol affects the engine performance by

A. causing corrosion of muffler and exhaust pipe
B. had odours
C. poor explosion characteristics
D. All of the above
E. None of the above
Answer» E. None of the above
Discussion
9.

Worn out carburettor jets are likely to cause

A. More noise
B. Excess fuel consumption
C. Knocking
D. Engine warm up
E. Excess engine output
Answer» C. Knocking
Discussion
10.

The firing order in case of four cylinder I.C. engine is given as

A. 1-2-3-4
B. 1-4-3-2
C. 1-2-4-3
D. none of the above
E. None of the above
Answer» D. none of the above
Discussion
11.

The knocking C.I engines is characterised by the sudden auto-ignition of the mixture

A. at the end of the combustion process
B. in the middle of combustion process
C. at the very beginning of the combustion process
D. none of the above
E. None of the above
Answer» D. none of the above
Discussion
12.

An opposed cylinder engine has

A. One crankshaft and two camshafts
B. One crankshaft and one camshafts
C. Two crankshafts and two camshafts
D. Two crankshafts and four camshafts
E. Two crankshafts and one camshaft
Answer» D. Two crankshafts and four camshafts
Discussion
13.

Which part is not common between the petrol and diesel engines

A. Battery
B. Dynamo
C. Air cleaner
D. Fuel injector
E. Exhaust silencer
Answer» E. Exhaust silencer
Discussion
14.

The substance which when added in a small proportion into petrol reduces knocking is

A. iso-butane
B. n-heptane
C. methyl nepthalene
D. tetra ethyl lead
E. None of the above
Answer» E. None of the above
Discussion
15.

The need for installing new piston rings is determined by checking

A. The gap between the ends of the ring
B. The clearance between cylinder and piston rings
C. The clearance between piston and piston rings
D. The clearance between cylinder and piston
E. The surface of the piston ring
Answer» C. The clearance between piston and piston rings
Discussion
16.

The air gap between the central electrode and ground electrode of a spark plug is approximately

A. 1 cm
B. 0.5 cm
C. 0.2 cm
D. 0.1 cm to 0.06 cm
E. None of the above
Answer» E. None of the above
Discussion
17.

Petrol engines are also known as

A. S.I. Engines
B. C.I. Engines
C. Steam Engines
D. none of the above
E. None of the above
Answer» B. C.I. Engines
Discussion
18.

Most of the mopeds in India have capacity of

A. 50 c.c.
B. 250 c.c.
C. 10 c.c.
D. 150 c.c.
E. 174 c.c.
Answer» B. 250 c.c.
Discussion
19.

Ignition quality of petrol is expressed by

A. Calorific value
B. Octane no
C. Cetane no
D. Mass/volume ratio
E. Alcohol
Answer» C. Cetane no
Discussion
20.

The king pin inclination is usually

A. Less than
B. Between 2? and 5?
C. More than 7?
D. More than 7?
E. Between 1? to 2?
Answer» C. More than 7?
Discussion
21.

Which of the following vehicle does not have battery?

A. Ambassador car
B. Maruti car
C. Vespa scooter
D. Tata truck
E. None of the above
Answer» D. Tata truck
Discussion
22.

Which of the following is a diesel engined vehicle?

A. Ambassador Mark II
B. Fiat 1100
C. Premier Padmini
D. Standard Gazel
E. None of the above
Answer» F.
Discussion
23.

In commercial vehicle layouts engine is located forward, rear or under floor mainly to

A. Minimize the tendency to over turn
B. Reduce the weight of chassis
C. Increase fuel economy
D. Better utilise the space
E. Have better weight distribution
Answer» F.
Discussion
24.

Which of the following is a front wheel drive vehicle?

A. Matador
B. Ambassador
C. Premier Padmini
D. Maruti
E. None of the above
Answer» E. None of the above
Discussion
25.

If brake wheels get locked before the vehicle stops, the vehicle is said to be

A. Rubbing
B. Slipping
C. Rolling
D. Skidding
E. Sliding
Answer» E. Sliding
Discussion
26.

In a vehicle the probable cause for hard steering could be

A. Low tyre pressure
B. Bent wheel spindle
C. Tie rod ends tight
D. Excessive castor
E. Any of the above
Answer» F.
Discussion
27.

Which tractor has an air cooled engine

A. Hindustan
B. HMT
C. Ford
D. Ferguson
E. Eicher
Answer» F.
Discussion
28.

Which is the Diesel engined vehicle

A. Ambassador Mark II
B. Premier padmini
C. Standard Gazel
D. Maruti
E. None of the above
Answer» F.
Discussion
29.

The device used to reduce the exhaust noise is known as

A. Exhaust manifold
B. Exhaust pipe
C. Tail pipe
D. Muffler
E. None of the above
Answer» E. None of the above
Discussion
30.

Engine oil is usually renewed after

A. 2500 - 6000 km
B. 24 km
C. 500 km
D. 100 km
E. 100 km
Answer» B. 24 km
Discussion
31.

In a Diesel engine the function of a fuel injector is

A. To mix fuel and air
B. To ignite air-fuel mixture
C. To provide adequate air fuel mixture for combustion
D. To provide flame front for ignition
E. To spray atomized fuel in the cylinder
Answer» F.
Discussion
32.

Automobile radiator is filled with

A. Hard water
B. Acidic water
C. Alkaline water
D. Rain water
E. Soft water
Answer» F.
Discussion
33.

The valve is opened as the cam lobe on the cam raises the

A. Piston pin
B. Valve lifter
C. Bearing
D. Valve guide
E. Valve seat
Answer» C. Bearing
Discussion
34.

The speed of the engine is increased or decreased by operating

A. Throttle valve
B. Choke valve
C. Steering
D. Clutch
E. Any of the above
Answer» B. Choke valve
Discussion
35.

When IHP and FHP on an engine are known, we can calculate

A. Mean effective pressure
B. Specific air consumption
C. Revolutions per minute
D. Brake horse power
E. Compression ratio
Answer» E. Compression ratio
Discussion
36.

The function of a governor in automobile is to

A. Limit the power
B. Maintain constant engine speed
C. Effect maximum fuel economy
D. Maintain constant engine speed when the vehicle speed changes
E. Limit the speed
Answer» F.
Discussion
37.

The angle during which both the inlet and exhaust valves remain open simultaneously, is known as

A. exhaust value angle
B. value angle
C. value overlap
D. none of the above
E. None of the above
Answer» D. none of the above
Discussion
38.

By supercharging

A. Power stroke becomes stronger
B. Loss in exhaust is reduced
C. Engine can be made to run smoother
D. Thermal efficiency of the engine can be improved
E. None of the above
Answer» E. None of the above
Discussion
39.

The term master cylinder is associated with

A. Braking system
B. Starting mechanism
C. Engine
D. Lubrication system
E. Cooling cylinder
Answer» B. Starting mechanism
Discussion
40.

Theoretical correct air-fuel ratio for tetrol engine is

A. 6 ; 1
B. 9 ; 1
C. 12 ; 1
D. 15 ; 1
E. 20 ; 1
Answer» E. 20 ; 1
Discussion
41.

As carbon accumulates in a cylinder it causes an increase in

A. Clearance volume
B. Ignition time
C. Volumetric efficiency
D. Piston displacement
E. Effective compression ratio
Answer» F.
Discussion
42.

Power assisted brakes are often provided on

A. motor cycles
B. air cooled engine vehicles
C. slow speed vehicles like road rollers etc.
D. heavy duty vehicles
E. None of the above
Answer» E. None of the above
Discussion
43.

The minimum cranking speed in petrol engines is

A. 2 - 3 rpm
B. Equal to the normal operating speed
C. 60 - 80 rpm
D. Half of operating speed
E. One fourth of operating speed
Answer» D. Half of operating speed
Discussion
44.

In a S.I. engine, when most economical mixture is supplied, the colour of exhaust flame is expected to be

A. Yellow-red to red
B. Dark red
C. Bluish, transparent
D. Dark blue to reddish-yellow
E. Colour of exhaust flame has nothing to do with the mixture composition
Answer» E. Colour of exhaust flame has nothing to do with the mixture composition
Discussion
45.

The firing order in case of four cylinder in-line engines is uaually

A. 1-2-4-3
B. 1-3-4-2
C. 1-4-3-2
D. Either (A) or (B)
E. Either (B) or (C)
Answer» F.
Discussion
46.

Ethyl fluid is used as

A. To improve lubricating quality of fuel
B. To increase octane rating of fuel
C. As a detonating agent
D. To increase cetane rotary of fuel
E. As a superior type of fluid compared to others
Answer» C. As a detonating agent
Discussion
47.

Mixing of fuel and air in case of a diesel engine occurs in

A. Injector
B. Engine cylinder
C. Inlet valve
D. Fuel pump
E. Inlet manifold
Answer» C. Inlet valve
Discussion
48.

Ignition advance in S.I. engine is not the direct function of

A. mixture strength
B. compression ratio
C. grade of petrol
D. load on engine
E. None of the above
Answer» E. None of the above
Discussion
49.

As a general rule if facing on the friction disc are worn down to the rivet heads

A. The clutch should be replaced
B. The linkage should be adjusted
C. Rivets head should be filed
D. Rivets should be replaced
E. The friction disc should be replaced
Answer» F.
Discussion
50.

In actual practice, the inlet value of a four stroke I.C. engine should open

A. exactly at the start of suction stroke
B. slightly after the start of suction stroke
C. slightly before the start of the suction stroke
D. none of the above
E. None of the above
Answer» D. none of the above
Discussion