Elements of Automobile Engineering Question Bank with

solution
(MCQs with Options and Answers)
The main structure supporting all automobile components is called:
a) Powertrain
b) Suspension system
c) Chassis
d) Steering mechanism

The component that converts chemical energy into mechanical energy in a vehicle is:
a) Battery
b) Differential
c) Internal combustion engine
d) Gearbox

Which system ensures controlled deceleration of a vehicle?

a) Suspension system
b) Steering system
c) Braking system
d) Transmission system

In SI engines, the ignition is produced by:

a) Heat of compression
b) Spark plug
c) Fuel injector
d) Air filter

A radiator is a part of which system?

a) Fuel system
b) Cooling system
c) Electrical system
d) Lubrication system

Which type of fuel is used in a Compression Ignition (CI) engine?

a) Petrol
b) Diesel
c) CNG
d) Hydrogen

The main purpose of a lubrication system in an engine is:

a) Cooling only
b) Reduce friction and wear
c) Control fuel flow
d) Supply air to combustion chamber

A turbocharger is driven by:

a) Crankshaft belt
b) Exhaust gases
c) Battery power
d) Lubrication pump

Which of the following is an alternative fuel for automobiles?

a) Leaded petrol
b) Kerosene
c) Hydrogen fuel cells
d) Crude oil

Engine block is commonly made from:

a) Copper
b) Cast iron or aluminum alloy
c) Plastic
d) Bronze

Which component connects and disconnects engine power from the wheels?
a) Gearbox
b) Differential
c) Clutch
d) Driveshaft

Which system allows the left and right wheels to rotate at different speeds during
turning?
a) Transmission system
b) Clutch
c) Differential
d) Axle

Which system provides shock absorption for a smoother ride?

a) Steering system
b) Suspension system
c) Braking system
d) Exhaust system

What type of steel is used in crash protection areas of a car?

a) Mild steel
b) Low carbon steel
c) Ultra High Strength Steel (UHSS)
d) Cast iron
 Friction stir welding is mainly used for:
a) Plastics
b) Joining aluminum parts
c) Glass panels
d) Rubber components

What is the function of a piston ring?

a) To connect piston to crankshaft
b) To open and close valves
c) To seal the piston and prevent oil leakage
d) To absorb engine vibrations

Which part distributes air or fuel-air mixture to the engine cylinders?

a) Exhaust manifold
b) Inlet manifold
c) Fuel pump
d) Carburetor

Which part collects burnt gases from engine cylinders and sends them to the exhaust
pipe?
a) Intake valve
b) Exhaust manifold
c) Spark plug
d) Flywheel

A vibration damper in an engine is used to:

a) Increase engine speed
b) Reduce engine vibrations
c) Supply lubrication
d) Adjust ignition timing

The primary function of wheels and tires is to:

a) Store energy
b) Support vehicle weight and provide road grip
c) Supply fuel
d) Lubricate moving parts

• Which type of battery is most commonly used in cars?

a) Nickel-cadmium
b) Lead-acid battery
c) Lithium-polymer
d) Dry cell

• The electrolyte in a lead-acid battery consists of:

a) Water only
b) Sulfuric acid and water
c) Sodium chloride solution
d) Alcohol-based fluid

• Which instrument is used to measure the density of battery electrolyte?

a) Voltmeter
b) Hydrometer
c) Ammeter
d) Tachometer

• Which component engages with the flywheel to crank the engine during starting?
a) Alternator
b) Starter motor
c) Fuel pump
d) Ignition coil

• In a petrol engine, ignition is achieved by:

a) Heat of compression
b) High-voltage spark
c) Exhaust gas pressure
d) Fuel injector spray only

• The purpose of fog lamps is:

a) Indicating vehicle turning direction
b) Improve visibility in foggy weather
c) Brake warning
d) Showing tail position

• Which sensor measures the oxygen content in exhaust gases?

a) Knock sensor
b) Throttle position sensor
c) Oxygen sensor
d) Speed sensor

• ECU in an automobile stands for:

a) Electronic Control Utility
b) Electronic Control Unit
c) Engine Computing Unit
d) Electrical Circuit Unit

• The alternator in a car is responsible for:

a) Fuel injection
b) Lubrication
c) Charging the battery and supplying power
d) Cooling the engine
• Trickle charging of a battery means:
a) Overcharging battery with high current
b) Maintaining full charge with small continuous current
c) Fast charging
d) Reverse charging process

Basics of Automobile

1. Explain the layout of an automobile and list its major components with their
functions.

a. The layout includes chassis (framework), powertrain (engine, transmission,

differential), suspension (absorbs shocks), braking system (controls speed
and stopping), steering system (direction control), electrical (battery, lights),
fuel, and cooling systems. Each ensures safe, efficient, and reliable operation.

2. Differentiate between SI (Spark Ignition) and CI (Compression Ignition)

engines with examples.

a. SI engines use spark plugs to ignite fuel-air mix, common in petrol cars. CI
engines use heat of compression to ignite diesel, found in heavy vehicles. SI
has higher RPM, CI higher torque and efficiency.

3. Describe the purpose of the cooling system and difference between air and
liquid cooling.

a. Cooling removes heat to prevent damage. Air cooling uses airflow and fins;
liquid cooling circulates coolant via pump and radiator for better
temperature control.

4. Explain the function of lubricants in an engine.

a. Lubrication minimizes friction, prevents wear, cools parts, reduces

corrosion, prolonging engine life.

5. Discuss main components of IC engine and their working.

a. Parts: Cylinder, piston, crankshaft, valves, spark plug/injector. Fuel burns in

cylinder producing gas pressure moving piston, rotating crankshaft
generating mechanical power.

6. Explain supercharging and turbocharging.

a. Both compress intake air for more fuel combustion. Supercharger driven by
engine, turbocharger by exhaust gases. Result: increased power and
efficiency.
7. List alternative fuels and discuss advantages and challenges.

a. CNG, LPG, electricity, biofuels, hydrogen. Advantages: low emissions,

renewable. Challenges: storage, high cost, limited infrastructure.

8. Effect of improper lubrication.

a. Leads to high friction, overheating, wear, seizing engine, performance loss.

9. Impact of overheating on engine.

a. Causes warping, gasket failure, oil degradation, loss of power, potential

breakdown.

10. Importance of material selection for engine parts.

a. Correct materials ensure strength, heat resistance. Example: Aluminum alloy

for weight reduction, cast iron for durability.

11. Ways to improve IC engine efficiency.

a. Turbocharging, high compression, better fuel injection, reduced friction,

advanced materials.

12. Biofuels eco-friendliness.

a. Renewable, low greenhouse gases, biodegradable, reduces fossil fuel

dependency.

13. Maintenance of cooling and lubrication systems.

a. Ensures optimum temperature, prevents wear, improves fuel economy,

extends life span.

14.

15. Define clutch and its role.

a. Temporarily disconnects engine from wheels for smooth gear change,

preventing gearbox damage.

16. Purpose of differential.

a. Allows wheels to turn at different speeds during cornering, preventing

skidding.

17. Use of high-strength steel and aluminum.

a. Improves crash safety, reduces weight, enhancing fuel economy.

18. Friction stir welding usage.

a. Joins aluminum car panels using frictional heat without melting.

19. Power transmission system flow.

a. Engine → Clutch → Gearbox → Driveshaft → Differential → Axle → Wheels.

Controls torque and speed effectively.

20. Role of piston rings, valves, vibration dampers.

a. Rings seal combustion, valves control intake/exhaust, dampers reduce noise

and vibration.

21. Inlet and exhaust manifolds function.

a. Inlet manifold distributes air/fuel to cylinders, exhaust manifold removes

gases, ensuring efficiency.

22. Effect of misalignment or faulty suspension.

a. Uneven tire wear, poor handling, unsafe driving.

23. Use of UHSS in crash zones.

a. Absorbs high impact energy, protects passengers.

24. Consequence of defective clutch.

a. Causes slipping, gear issues, reduced performance, gearbox damage.

25. Lightweight materials improve efficiency.

a. Less mass reduces fuel consumption. Example: Aluminum body panels.

26. Improve welding strength.

a. Use hybrid/laser welding, strict quality checks.

27. Proper design reduces vibration and noise.

a. Balanced shafts, dampers, precision components reduce NVH.

28.

29. Battery purpose and components.

a. Stores electrical energy for starting engine, powers accessories.

Components: plates, electrolyte, separators, terminals.

30. Define lead-acid battery and electrolyte role.

 a. Lead plates react with sulfuric acid solution to generate electricity.

31. Trickle charging.

a. Low constant current keeps battery fully charged, prevents discharge.

32. Starter motor function.

a. Engages flywheel to crank engine for starting combustion.

33. Battery health tests.

a. Voltage test checks state of charge, load test checks current capacity,
hydrometer measures electrolyte density for charge status.

34. Ignition system of petrol engine.

a. Coil boosts voltage, ECU or distributor controls timing, spark plug ignites
mix, ensuring proper combustion.

35. Sensors and ECU role.

a. Sensors (oxygen, throttle, knock) send data to ECU controlling fuel injection
and emissions.

36. Impact of weak battery.

a. Causes starting issues, dim lights, ECU malfunctions, safety hazards.

37. Role of oxygen sensors.

a. Optimize air-fuel ratio, ensure complete combustion, reduce harmful

emissions.

38. Battery safety precautions.

a. Wear gloves, goggles, avoid sparks, disconnect negative terminal first.

39. Alternator role in running vehicle.

a. Converts mechanical energy to electricity, charges battery, powers systems.

40. Improvement in battery technology.

a. Use lithium-ion, solid-state, faster charging, higher energy density.

41. Automation enhances safety and comfort.

a. Automated lights, ABS, airbags, sensors increase safety and driving comfort