A traction control system (TCS) in automobiles controls the
1.Vibrations on the steering wheel
2.Engine power during acceleration
3.Torque that is transmitted by the tyres to the road surface
4.Stopping distance in case of emergency
During braking, the brake shoe is moved outward to force the lining against the
1.Wheel piston or cylinder
2.Anchor pin
3.Brake drum
4.Wheel rim or axle
For the same maximum pressure and temperature
1.Diesel cycle is more efficient than Otto cycle
2.Otto cycle is more efficient than Diesel cycle
3.Both Otto cycle and Diesel cycle are equally efficient
4.None of the above
If the air-fuel mixture ignites before the spark takes place at spark plug, the condition is called
1.Detonation
2.Ignition
3.Pre-ignition
4.Rumble
If the engine coolant leaks into the engine oil, then engine oil
1.Appears milky
2.Become foamy
3. Turns black
4.None of these
In a four stroke engine for each crankshaft revolution, the camshaft revolves
1.One half turn
2. One turn
3.Two turns
4.Four turns
In a petrol engine, the high voltage for spark plug is in the order of
1.1000 volts
2. 2000 volts
3.11 kilovolts
4.22 kilovolts
In automobiles G.V.W. refers to
1. Gross vehicle width
2. Gross vehicle weight
3.Gross vehicle wheel base
4.Gross vehicle wheel track
In radial tyres
1.One ply layer runs diagonally one way and another layer runs diagonally the other way
2.All plies run parallel to one another and vertical to tyre bead
3. Inner tubes are always used
4.None of these
The capacity of a battery is usually expressed in terms of
1.Volts
2.Amperes
3.Weight
4.Ampere hours
The cetane number of a Diesel fuel is a measure of
1.Volatility
2.Viscosity
3. Ignition quality
4.Delay period
The cetane rating of Diesel fuel is in the order of
1.25
2.45
3.70
4.90
The characteristic that is enhanced by the honing of cylinder sleeves inner surface is
1. Cooling efficiency (B)(C) (D) None of these
2. Resistance to wear
3.Lubrication performance
4.None of these
The component in the radiator of an automobile that increases the boiling point of water is
1.Drain plug
2.Water jacket
3.Vacuum valve
4.Pressure cap
The composition of the electrolyte in a fully charged battery is that
1.The electrolyte is pure distilled water
2.The electrolyte is pure sulphuric acid
3.The electrolyte is a mixture of 64% distilled water and 36% sulphuric acid by weight
4.The electrolyte is a mixture of 90% distilled water and 10% sulphuric acid by weight
The condition that results in large quantities of HC emission is
1.High temperature combustion
2.Incomplete combustion
3.Low temperature combustion
4. High atmospheric temperature combustion
The difference between DOT 3 and DOT 4 brake fluids is
1.DOT 4 fluids have a higher boiling point than DOT 3 fluid
2.DOT 4 fluids have a lower boiling point than DOT 3 fluid
3.DOT 3 and DOT 4 fluids have the same boiling point, but DOT 4 fluid has a longer service life
4.DOT 4 fluid is more resistant to freezing than DOT 3 fluid
The function of a first compression ring (top ring) is that it
1.Increases the combustion temperature
2.Creates swirl
3.Maintains a seal and prevents the fuel leakage
4.Maintains a seal and prevents escape of burned gases and loss of pressure in the combustion chamber
The main merit of a multi cylinder type cylinder sleeve is
1. Smaller engine dimensions
2.Better cooling efficiency
3.High rigidity
4. None of these
The octane rating of petrol commercially available is
1. 85-95
2. 95-100
3. 100-110
4. 110-125
The path taken by intake air is
1.Carburettor (or throttle body) air cleaner intake manifold intake ports cylinders
2. Air cleaner carburettor (or throttle body) intake ports intake manifold cylinders
3.Air cleaner intake manifold carburettor (or throttle body) intake ports cylinders
4.Air cleaner carburettor (or throttle body) intake manifold intake ports cylinders
The petrol engines are also known as
1.Spark ignition (S.I.) engines
2.Compression ignition (C.I.) engines
3. Steam engines
4.None of these
The starter motor is driven by
1.Chain drive
2.Gear drive
3.Flat belt drive
4.V-belt drive
The torque available at the contact between driving wheels and road is known as
1.Brake effort
2.Tractive effort
3.Clutch effort
4. None of these
A clutch is usually designed to transmit maximum torque which is
1.Equal to the maximum engine torque
2.80% of the maximum engine torque
3. 150% of the maximum engine torque
4.None of these
A four cylinder engine has a capacity of 2.4 litres. The swept volume of one cylinder is
1. 400 cm³
2.600 cm³
3.1200 cm³
4.2400 cm³
A petrol engine of a car develops 125 Nm torque at 2700 r.p.m. The car is driven in second gear having gear ratio of 1.75. The final drive ratio is 4.11. If the overall transmission efficiency is 90%, then the torque available at the driving wheels is
1.8.091 Nm
2.80.91 Nm
3.809.1 Nm
4.8091 Nm
An engine has a clearance volume of 100 cm³ and a swept volume of 800 cm³. The compression ratio is
1. 7 : 1
2. 8 : 1
3. 9 : 1
4. 10 : 1
Highest useful compression ratio (HUCR) is the highest compression ratio at which the
1.Engine can run
2.Engine gives maximum output
3.Engine is most efficient
4.Fuel can be used in a test engine without knocking
In a square type engine
1.Geometrical shape is square
2.Diameter and length of piston are same
3.Two cylinders are placed horizontal and two vertical
4. Stroke length and cylinder bore are same
In a ventilated disc brake
1. A duct directs air towards the caliper for cooling while the vehicle is moving
2. Caliper is covered with cooling fins
3.Disc contains many small holes for optimum cooling performance
4.Disc contains radial vanes between its rubbing surfaces for optimum cooling performance
In comparison with a radial tyre, one advantage of a bias ply tyre is
1. Longer life
2.Lower rolling resistance
3.Smoother ride at low speeds
4. None of these
In Diesel engines, during suction stroke, _________ is drawn in the cylinder.
1.Air and fuel
2.Only fuel
3.Only air
4.None of these
In petrol engines, during suction stroke, _________ is drawn in the cylinder
1.Air and fuel
2.Only fuel
3.Only air
4.None of these
It is necessary to maintain the valve clearances as they
1.Reduce the resistance to sliding that occurs between the cam and the tappet (B) (C) (D)
2.Allow for lengthening of the valves owing to the heat of combustion
3.Increase the speed at which the valves move up and down
4.Make the crankshaft turn smoothly
The acid used in automobile battery is
1.Hydrochloric acid
2.Hydrofluoric acid
3. Nitric acid
4.Sulphuric acid
The air gap between the central electrode and ground (or side) electrode of a spark plug is around
1.0.2 mm
2.0.5 mm
3.1 mm
4.1.5 mm
The air resistance to a car at 20 kmph is R. The air resistance at 40 kmph will be
1.R
2.2R
3.4R
4.4R²
The auto ignition in a spark ignition engine means
1.Automatic ignition of the charge at the end of compression
2.Ignition induced by the passage of a spark
3.Ignition of the charge before the passage of flame front
4. Ignition induced to supplement the process of normal combustion
The ball joints are used on the tie rod ends, because they
1.Reduce the amount of noise generated
2.Reduce the amount of sliding resistance
3.Can deal with movement of the suspension both vertically and in other directions
4.Improve the force transmission speed
The basic purpose of tyres is to
1. Grip the road and provide good traction
2.Substitute for springs
3. Act as brake
4.None of these
The brake warning light warns the driver of
1.The brake warning light warns the driver of
2.Air in the hydraulic system
3.Failure of the primary or secondary circuit of hydraulic system
4.Power brake failure
The braking control type traction control system (TCS) generally operates in the speed range of
1.Less than 20 kmph
2.Less than 40 kmph
3.Less than 60 kmph
4. More than 60 kmph
The calorific value of petrol is about
1.36.5-38.5 MJ/kg
2.39.4-42.5 MJ/kg
3.42.7-43.5 MJ/kg
4.45.5-47 MJ/kg
The clutch is located between the transmission and the
1.Engine
2.Rear axle
3.Propeller shaft
4.Differential
The coefficient of friction for the clutch facing is approximately
1.0.1
2.0.4
3.0.8
4.1.2
The component of the oil filter that prevents the passage of metal particles and sludge is
1.Element
2.Relief valve
3. Check valve
4.Case
The component that connects the steering rack to the knuckles is
1.Tie rod
2. Sector gear
3.Pivot
4.Spline
The compression ratio of a petrol engine is nearly
1.4:1
2.1
3.15:1
4.20:1
The connecting rods are generally made of __________ shaped cross-section.
1.I
2.C
3.L
4.H
The crankshaft of a typical inline four cylinder engine has ________ balance weights.
1.12
2.4
3.16
4.8
The diagram which shows the correct crank positions corresponding to the opening and closing of the valves, is known as
1.Indicator diagram
2.Axial force diagram
3.Valve timing diagram
4.None of these
The drive-shafts are connected to the differential and wheel hubs through universal joints because the universal joints
1.Absorb the vibrations transferred from the surface of the road
2.Compensate for variations in the relative positions of the differential and the wheels which result from bumpy road surfaces or other similar driving conditions.
3. Absorb any difference in speed between the left and right wheels when the vehicle is turning
4. None of the above
The engine oil level should be checked
1. Immediately after the ignition switch is turned off
2. While the engine is running
3.A few minutes after the ignition switch is turned off
4.While the engine is running at high idle speed
The engine oil viscosity is defined by ___________ ratings.
1.Automatic transmission fluid (ATF)
2. Society of automotive engineers (SAE)
3.Gross vehicle weight (GVW)
4.American petroleum institute (API)
The formula for Iso-octane is
1.C8H18
2.C7H17
3.C6H18
4.C7H18
The instrument used to check specific gravity of acid in a battery is
1.Hydrometer
2.Hygrometer
3.Anemometer
4.Multimeter
The main feature of Macpherson strut suspension is that
1.The vertical size of the suspension can be made more compact
2. Non vertical external forces are supported by the suspension arms
3.The unsprung mass in lighter
4.The assembly is slightly more complicated in design
The main function of an exhaust muffler is the
1. Optimization of exhaust efficiency
2. Reduction of exhaust noise
3.Reduction of nitrogen oxide in the exhaust gases
4.Reduction of the exhaust gas volume
The maximum torque multiplication ratio in a torque converter is about
1. 2.5
2.10
3.25
4.40
The most commonly used power plant in automobiles is
1.Gas turbine
2. I.C. engine
3.Battery
4.None of these
The negative plates of a lead acid battery has
1.Lead peroxide (PbO₂)
2.Spongy lead (Pb)
3. Sulphuric acid (H₂SO₄)
4.Lead sulphate (PbSO₄)
The painting of automobiles is done to
1. Prevent rust from growing on the body
2.Improve its external appearance
3.Retain the characteristics of steel for long
4. All of these
The petrol engine works on
1.Otto cycle
2.Carnot cycle
3.Diesel cycle
4.Rankine cycle
The positive plates of a lead acid battery has
1.Lead peroxide (PbO₂)
2.Spongy lead
3.ead sulphate L(PbSO₄)
4.Sulphuric acid (H₂SO₄)
The problems caused by the wheel imbalance are
1.Hard steering and hard ride
2.Poor acceleration and hard steering
3.Steering wheel vibrations and uneven tyre wear
4.Poor acceleration and reduced fuel efficiency
The rigid suspension is beneficial when
1.It is desired to reduce the unsprung mass
2. It is desired to have more flexibility in design
3.It is desired to improve tyre to ground contact characteristics
4.Large changes in load make it necessary to have a large suspension stroke
The size of engine cylinder is referred in terms of its
1. Diameter and bore
2. Displacement and efficiency
3.Bore and stroke
4.Bore and length
The stroke of an engine is the
1.Volume of the cylinder
2. Length of the connecting rod
3.Internal diameter of the cylinder
4.Distance between T.D.C. and B.D.C.
The tilting of the front wheels away from the vertical, when viewed from the front of the car, is called
1.Camber
2.Caster
3.Toe in
4.Toe out
The torque converter uses ________ to transfer torque.
1.Air
2.Automatic transmission fluid (ATF)
3.Gears
4.Steel belt
The vehicle ride will be comfortable if
1.Unsprung mass is kept minimum
2.Sprang mass is kept minimum
3.Vehicle mass is kept minimum
4.All of these
Thinner is added to the paint in order to
1. Make pigments and resin mix easily
2. Make paint film hard
3.Optimise its viscosity
4.None of these
When the battery is half (50%) charged, the specific gravity of acid in a battery is usually
1.0.74
2.1.00
3.1.12
4.1.19
When the brake pedal free play is less than the specified value, then the
1.Brake drags
2.Vapour locking occurs in the brake lines
3.Brake fades
4.Antilock braking system malfunctions