Explore topic-wise MCQs in Mechanical Engineering.

This section includes 538 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

The air resistance to a car at 20 kmph is . The air resistance at 40 kmph will be

A. 2
B. 4
C. 4
Answer» D.
2.

The main feature of MacPherson strut suspension is that

A. the vertical size of the suspension can be made more compact
B. non-vertical external forces are supported by the suspension arms
C. the unsprung mass in lighter
D. the assembly is slightly more complicated in design
Answer» C. the unsprung mass in lighter
3.

When indicated power (..) and frictional power (..) are known, we can calculate

A. brake power
B. compression ratio
C. specific air consumption
D. mean effective pressure
Answer» B. compression ratio
4.

An engine has a clearance volume of 100 cm and a swept volume of 800 cm. The compression ratio is

A. 7:1
B. 8:1
C. 9:1
D. 10:1
Answer» D. 10:1
5.

In a Diesel engine, the fuel is ignited by

A. an electric spark
B. the heat of compression
C. the hot exhaust
D. none of these
Answer» C. the hot exhaust
6.

The information provided by the oxygen (O) 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
7.

The firing order in the case of a four-cylinder I.C. engine (inline) 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
8.

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» B. Headlights and other electrical devices are switched on.
9.

Which of the following bulb in a car will have the least wattage ?

A. Head light bulb
B. Stop light bulb
C. Parking light bulb
D. Ignition warning bulb
Answer» E.
10.

The engine's idling speed will increase by a slight degree immediately after a cold engine has been started. It will drop as the engine warms up. and it will eventually reach the standard level.

A. True
B. False
Answer» B. False
11.

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» C. 900
12.

The function of antilock brake system (ABS) is that is

A. reduces the stopping distance
B. minimises 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
13.

The minimum parking brake force is generally __________ of gross vehicle mass (GVM).

A. 5%
B. 10%
C. 15%
D. 20%
Answer» E.
14.

When turning a corner,

A. the front wheels are toeing out
B. the front wheels are turning on different angles
C. the inside front wheels has a greater angle than the outside wheel
D. all of the above
Answer» E.
15.

Toe-in ensures parallel rolling of the wheel thus stabilizing steering in addition to preventing both sides slipping and excessive tyre wear.

A. Correct
B. Incorrect
Answer» B. Incorrect
16.

If a tyre is designated as 175/65 R14 82 S, then the aspect ratio for the tyre is

A. 175
B. 65
C. 14
D. 82
Answer» C. 14
17.

In comparison with a radial tyre, one advantage of a bias-ply tyre is

A. longer life
B. lower rolling resistance
C. smoother ride at low speeds
D. none of these
Answer» D. none of these
18.

An over-inflated tyre will wear the tread most near the

A. edges
B. corners
C. centre
D. none of these
Answer» D. none of these
19.

Which part of the automobile tyre is subjected to greatest flexing action ?

A. Bead
B. Side wall
C. Shoulder
D. Tread
Answer» C. Shoulder
20.

Which of the following parameter can be adjusted by modifying the tie-rod attachment length ?

A. Camber
B. Caster
C. Toe
D. Steering gear ratio
Answer» D. Steering gear ratio
21.

The ball joints are used on the tie-rod ends, because they

A. reduce the amount of noise generated
B. reduce the amount of sliding resistance
C. can deal with movement of the suspension both vertically and in other directions
D. improve the force transmission speed
Answer» D. improve the force transmission speed
22.

Two speed reverse gear arrangement is generally provided in case of

A. passenger cars
B. metadors
C. tractors
D. trucks
Answer» D. trucks
23.

Which of the following is not a part of the chassis ?

A. Wheels
B. Front axle
C. Steering system
D. Seats
Answer» E.
24.

In a four wheel drive (4WD), the number of gear boxes are

A. 1
B. 2
C. 3
D. 4
Answer» C. 3
25.

The major purpose of an electronically-controlled automatic transmission is that this type of transmission

A. eliminates gear clutches
B. eliminates the gear shift lever
C. reduces the number of automatic-transmission components
D. reduces shift shock and achieves more efficient transmission of engine torque
Answer» E.
26.

The differential ensures that each wheel is driven at a speed which corresponds to the distance it must travel around a corner, and it consequently prevents against excessive tyre wear.

A. Agree
B. Disagree
Answer» B. Disagree
27.

When cornering, the differential generates a difference in the speed of the left and right wheels.

A. True
B. False
Answer» B. False
28.

The smooth shift mechanism of an automatic transmission reduces the degree of shock at shifting of gears.

A. Yes
B. No
Answer» B. No
29.

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.
30.

The torque converter uses __________ to transfer torque.

A. air
B. automatic transmission fluid (ATF)
C. gears
D. steel belt
Answer» C. gears
31.

The driveshafts are connected to the differential and wheel hubs through universal joints because the universal joints

A. absorb the vibrations transferred from the surface of the road
B. compensate for variations in the relative positions of the differential and the wheels which result from bumpy road surfaces or other similar driving conditions.
C. absorb any difference in speed between the left and right wheels when the vehicle is turning
D. none of the above
Answer» C. absorb any difference in speed between the left and right wheels when the vehicle is turning
32.

Which one of the following statements correctly describes the construction of a planetary gear type differential ?

A. The six planetary pinions rotate in constant mesh with the internal gears.
B. One drive shaft is splined to the central gear and the other to the planetary gear.
C. Each planetary pinion gear meshes with both the central gear and the internal gear.
D. The internal gear is fixed to the planetary gear.
Answer» C. Each planetary pinion gear meshes with both the central gear and the internal gear.
33.

Which one of the following statement correctly describe the construction of a bevel-gear type differential?

A. The drive shafts are splined to the differential carrier.
B. The left side gear and the differential carrier rotate in constant unison.
C. The differential carrier houses differential pinion gears and side gears, each pinion gear meshes with a different side gear.
D. The differential carrier houses differential pinion gears and side gears
Answer» E.
34.

When the vehicle is at rest, the clutch is in engaged position.

A. Correct
B. Incorrect
Answer» B. Incorrect
35.

The seat belt will move out smoothly when pulled out slowly, but it will lock when pulled quickly.

A. Agree
B. Disagree
Answer» B. Disagree
36.

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

A. sharp edged fragments
B. small particles
Answer» C.
37.

The main characteristics of a maintenance-free (MF) battery is that

A. a maintenance-free battery requires little maintenance during normal use and it is sufficient to add water instead of an electrolyte containing sulphuric acid
B. a maintenance-free battery has a relatively short shelf life when compared with standard batteries
C. since it is sealed, the water in a maintenance-free battery is not lost through evaporation thus accordingly it is not necessary to top up the cells with water
D. recharging of a maintenance-free battery is neither required nor possible
Answer» D. recharging of a maintenance-free battery is neither required nor possible
38.

The discharged lead-acid battery has on its plates

A. lead peroxide (PbO2)
B. spongy lead (Pb)
C. lead sulphate (PbSO4)
D. sulphuric acid (H2SO4)
Answer» D. sulphuric acid (H2SO4)
39.

How many cells are used in a 12 volt car battery ?

A. 2
B. 4
C. 6
D. 8
Answer» D. 8
40.

The number of exhaust manifolds in a V-6 engine are

A. one
B. two
C. four
D. eight
Answer» C. four
41.

Which of the following oil is more viscous ?

A. SAE 30
B. SAE 40
C. SAE 70
D. SAE 80
Answer» E.
42.

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)
43.

The engine oil is stored in __________ when the engine is not running.

A. oil pan
B. cylinder head
C. oil pump
D. separate oil tank
Answer» B. cylinder head
44.

The forced-fed lubrication system means that the oil is delivered to the engine by

A. gravity
B. the pressure created by the oil pump
C. splashing action of the crankshaft
D. none of these
Answer» C. splashing action of the crankshaft
45.

The indicated power of a four-stroke engine (in watts) is equal to (where P = Mean effective pressure in N/m2, L = Length of stroke in metres, A = Cross-sectional area of the piston in m2, and N = Speed of the engine in revolutions per second (r.p.s))

A. P.L.A.N/2
B. P.L.A.N
C. 2 x P.L.A.N
D. P.L.A.N/4
Answer» B. P.L.A.N
46.

The function of a carburettor is to control the amount and ratio of air-fuel mixture.

A. True
B. False
Answer» B. False
47.

The anti-knock property of compression ignition engine fuel can be improved by adding

A. tetraethyl lead
B. trimethyl pentane
C. amyl nitrate
D. hexadecane
Answer» D. hexadecane
48.

When the engine speed increases, the ignition timing must be advanced.

A. Yes
B. No
Answer» B. No
49.

The process of removing the burnt gases from the engine cylinder by the fresh charge coming into the engine cylinder from the crank-case, is known as

A. cleaning
B. priming
C. scavenging
D. detonation
Answer» D. detonation
50.

The information provided by the oxygen (O2) 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