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.

The main task of a battery in automobiles is to

A. Supply electricity to the alternator
B. Act as a reservoir or stabilizer of electricity
C. Supply electricity to the vehicle's electrical system at all times while the engine is running
D. Supply a large amount of power to turn the starter motor when the engine is being started
Answer» E.
2.

When the battery is half (50%) charged, the specific gravity of acid in a battery is usually

A. 0.74
B. 1.00
C. 1.12
D. 1.19
Answer» E.
3.

Highest useful compression ratio (HUCR) is the highest compression ratio at which the

A. Engine can run
B. Engine gives maximum output
C. Engine is most efficient
D. Fuel can be used in a test engine without knocking
Answer» E.
4.

A laminated glass upon cracking

A. Bursts into sharp edged fragments
B. Bursts into granular pieces
C. Sandwiched layer traps the fragments
D. Breaks into the form of crystals
Answer» D. Breaks into the form of crystals
5.

The self ignition temperature of Diesel as compared to petrol is

A. Higher
B. Lower
C. Same
D. Depends on fuel quality
Answer» C. Same
6.

The Diesel engines are also known as

A. Spark ignition (S.I.) engines
B. Compression ignition (C.I.) engines
C. Steam engines
D. None of these
Answer» C. Steam engines
7.

The petrol engines are also known as

A. Spark ignition (S.I.) engines
B. Compression ignition (C.I.) engines
C. Steam engines
D. None of these
Answer» B. Compression ignition (C.I.) engines
8.

A worm gear is used as the pinion for the rack and pinion type of steering gearbox, because it

A. Improves steering comfort when steering wheel is turned to effect small changes in the direction of forward motion
B. Allows the steering wheel to be turned by a greater amount when steering
C. Makes the steering more responsive
D. Reduces the amount of kickback for large steering angles
Answer» B. Allows the steering wheel to be turned by a greater amount when steering
9.

An under-inflated tyre will wear the tread most

A. Near the centre
B. Near the edges
C. In the lateral direction
D. In the cross direction
Answer» C. In the lateral direction
10.

The purpose of a balancer shaft is to

A. Balance the timing in the movement of the two groups of pistons
B. Increase inertia force of the rotating crankshaft
C. Reduce vibrations caused by the crankshaft rotation
D. Adjusts the timing of the intake and exhaust valve openings
Answer» D. Adjusts the timing of the intake and exhaust valve openings
11.

The correct way to rectify an imbalanced wheel is to

A. Adjust the tyre pressure
B. Rotate the tyres
C. Adjust the damper spring tension
D. Attach appropriate weights to the wheel at appropriate positions
Answer» E.
12.

A maintenance free battery

A. Has lead-antimony plate grid
B. Has lead-calcium plate grid
C. Does not contain acid
D. Does not contain water
Answer» C. Does not contain acid
13.

If the spark plug deposit indicates black coating of soot, it indicates that the engine has been generally operating on

A. Too lean mixture
B. Stoichiometric mixture
C. Most economical mixture
D. Too rich mixture
Answer» E.
14.

The octane rating of petrol commercially available is

A. 85-95
B. 95-100
C. 100-110
D. 110-125
Answer» B. 95-100
15.

Which of the following symptom is caused as a result of brake disc run out?

A. Ineffectiveness of the brakes
B. Judder during braking
C. Localized wearing of the brake pads
D. Rapid wearing of the brake pads
Answer» C. Localized wearing of the brake pads
16.

The camshaft of a four stroke Diesel engine running at 1000 rpm will run at

A. 500 rpm
B. 1000 rpm
C. 2000 rpm
D. 4000 rpm
Answer» B. 1000 rpm
17.

The engine oil viscosity is defined by ___________ ratings.

A. Automatic transmission fluid (ATF)
B. Society of automotive engineers (SAE)
C. Gross vehicle weight (GVW)
D. American petroleum institute (API)
Answer» C. Gross vehicle weight (GVW)
18.

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» E.
19.

A heat treated glass generally used in automobiles bursts into ________ upon cracking,

A. Sharp edged fragments
B. Small particles
C. Large particles
D. None of these
Answer» C. Large particles
20.

The connecting rod lower end is connected to the relevant ________ of crankshaft.

A. Big end
B. Crank arm
C. Journal
D. Small end
Answer» D. Small end
21.

The positive plates of a lead acid battery has

A. Lead peroxide (PbO₂)
B. Spongy lead (Pb)
C. Lead sulphate (PbSO₄)
D. Sulphuric acid (H₂SO₄)
Answer» B. Spongy lead (Pb)
22.

The negative plates of a lead acid battery has

A. Lead peroxide (PbO₂)
B. Spongy lead (Pb)
C. Lead sulphate (PbSO₄)
D. Sulphuric acid (H₂SO₄)
Answer» C. Lead sulphate (PbSO₄)
23.

Wheel base of a vehicle is the

A. Distance between the centres of the front and rear wheels
B. Distance between the centres of the front tyres
C. Distance between the centres of the rear tyres
D. Extreme length of the vehicle
Answer» B. Distance between the centres of the front tyres
24.

The basic characteristics of a brake fluid is

A. A high boiling point
B. Low viscosity
C. Compatibility with rubber and metal parts
D. All of these
Answer» E.
25.

The function of anti-lock brake system (ABS) is that is

A. Reduces the stopping distance
B. Minimizes the brake fade
C. Maintains directional control during braking by preventing the wheels from locking
D. Prevents nose dives during braking and thereby postpones locking of the wheels
Answer» D. Prevents nose dives during braking and thereby postpones locking of the wheels
26.

In a fuel injection system, the electronic control module (ECM) calculates the optimum fuel-injection volume for the engine condition based on the data received from the sensors, and injects this volume of fuel into the intake manifold at the optimum timing.

A. Correct
B. Incorrect
C. -
D. -
Answer» B. Incorrect
27.

The coefficient of friction for the clutch facing is approximately

A. 0.1
B. 0.4
C. 0.8
D. 1.2
Answer» C. 0.8
28.

Which of the following indicates a multigrade oil ?

A. SAE 30
B. API SF
C. SAE 20 W-50
D. API 50
Answer» D. API 50
29.

The valve overlap in four stroke petrol engines is approximately

A. 30°
B. 60°
C. 90°
D. 120°
Answer» B. 60°
30.

The cetane number of a Diesel fuel is a measure of

A. volatility
B. viscosity
C. ignition quality
D. delay peirod
Answer» E.
31.

The air gap between the central electrode and ground (or side) electrode of a spark plug is around

A. 0.2 mm
B. 0.5 mm
C. 1 mm
D. 1.5 mm
Answer» D. 1.5 mm
32.

The cetane rating of Diesel fuel is in the order of

A. 25
B. 45
C. 70
D. 90
Answer» C. 70
33.

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

A. 200 bar
B. 220 bar
C. 250 bar
D. 300 bar
Answer» B. 220 bar
34.

The most commonly used supplementary restraint system (SRS) component is

A. seat belt
B. brake
C. airbag
D. steering
Answer» D. steering
35.

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

A. it makes petrol engines lighter
B. higher or equivalent compression ratio in petrol engines is not possible due to pre-ignition
C. less compression ratio gives better performance
D. it is just customary to have less compression ratio in petrol engines
Answer» C. less compression ratio gives better performance
36.

The aluminium alloy is used in cylinder blocks because

A. it is lighter and have good heat dissipation characteristics
B. material cost is low
C. it does not require any cylinder liners
D. the piston is also made of aluminium alloy
Answer» B. material cost is low
37.

The operation of removing trapped air from the hydraulic braking system is known as

A. trapping
B. tapping
C. bleeding
D. cleaning
Answer» D. cleaning
38.

The battery is an electrochemical device, which means battery

A. makes chemicals by mechanical means
B. uses chemical action to provide electricity
C. has curved plates instead of flat plates
D. does not use an electrolyte
Answer» C. has curved plates instead of flat plates
39.

The diagram which shows the correct crank positions corresponding to the opening and closing of the valves, is known as

A. indicator diagram
B. axial force diagram
C. valve timing diagram
D. none of these
Answer» D. none of these
40.

The information provided by the oxygen (O 2 ) sensor to the feedback control system is about the

A. air-fuel ratio
B. air temperature
C. air flow speed
D. exhaust gas volume
Answer» B. air temperature
41.

If the air-fuel mixture ignites before the spark takes place at spark plug, the condition is called

A. detonation
B. ignition
C. pre-ignition
D. rumble
Answer» D. rumble
42.

If the level of tension in the belt is too high, it can result in a loss of power or in bending of the rotating shaft or crankshaft.

A. Correct
B. Incorrect
C. -
D. -
Answer» B. Incorrect
43.

The co-efficient 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» E.
44.

The advantage of double-wishbone suspension design is that a large amount of freedom is available for setting geometry and precise settings can be made for driving comfort and steerability,

A. Correct
B. Incorrect
C. -
D. -
Answer» B. Incorrect
45.

If the air-fuel mixture in a spark ignition engine is too rich, then air-fuel ratio is about

A. 17:1
B. 15:1
C. 13:1
D. 10:1
Answer» E.
46.

The effect of having excess camber is

A. excessive steering alignment torque
B. hard steering
C. too much traction
D. uneven tyre wear
Answer» E.
47.

In a ventilated disc brake,

A. a duct directs air towards the caliper for cooling while the vehicle is moving
B. caliper is covered with cooling fins
C. disc contains many small holes for optimum cooling performance
D. disc contains radial vanes between its rubbing surfaces for optimum cooling performance
Answer» E.
48.

The firing order for an in-line four cylinder I.C. engine is

A. 1-2-3-4
B. 1-3-4-2
C. 1-2-4-3
D. 1-3-2-4
Answer» C. 1-2-4-3
49.

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» C. gross vehicle wheel base
50.

Positive camber is used to compensate for wheels tilting inward due to the weight of the vehicle.

A. Yes
B. No
C. -
D. -
Answer» B. No