Grade 10 power mechanics – Motor Vehicle Chassis Quiz

1. What is the main purpose of the vehicle chassis (frame)?

To support the vehicle body and major components such as engine and suspension
To increase the size of the engine cylinders
To cool the engine coolant more quickly
To control the fuel air mixture entering the engine
Explanation:

The chassis (frame) provides the structural support for the body, engine, suspension and other components, keeping the vehicle rigid and maintaining alignment.

2. Which type of suspension commonly uses layers of curved metal strips bolted together?

Leaf spring suspension
Air suspension
Hydropneumatic suspension
Coil spring suspension
Explanation:

Leaf springs are made from stacked, curved steel plates (leaves) and are traditional on many trucks and older vehicles for supporting loads.

3. Which component absorbs and controls unwanted bouncing and oscillation of the vehicle's springs?

Shock absorber (damper)
Wheel hub
Radiator fan
Brake caliper
Explanation:

Shock absorbers dampen spring motion, converting kinetic energy into heat to control bouncing and provide a smoother ride.

4. What is the main difference between a live axle and a dead axle?

A live axle is only used on motorcycles and a dead axle on cars
A live axle cannot be used on four-wheel drive vehicles
A live axle transmits driving torque to the wheels while a dead axle only supports the vehicle weight
A live axle is always made of aluminium and a dead axle is made of steel
Explanation:

A live axle carries driving torque to the wheels (often rear axle on driven vehicles), whereas a dead axle is a non-driven support for wheels.

5. Which steering system is commonly used in modern small cars for its simplicity and precision?

Chain-driven steering
Steering box with worm and sector
Belt and pulley steering
Rack and pinion steering
Explanation:

Rack and pinion steering gives direct, precise control and is compact, making it common in modern small cars.

6. What does wheel alignment adjustment change to improve tyre wear and handling?

Brake lining thickness
Camber, caster and toe angles
Engine timing and idle speed
Fuel injector spray pattern
Explanation:

Alignment adjustments change camber, caster and toe to ensure tyres contact the road correctly, reducing uneven wear and improving handling.

7. Which type of brake uses a hydraulic piston to squeeze pads against a spinning disc?

Mechanical shoe brake
Disc brake
Drum brake
Band brake
Explanation:

Disc brakes use hydraulic pistons to clamp brake pads onto a rotor (disc), providing effective stopping power and good heat dissipation.

8. What is the purpose of the differential in the rear axle of a vehicle?

To allow the driven wheels to rotate at different speeds while cornering
To pump more oil into the engine
To increase the fuel efficiency of the engine directly
To connect the engine to the battery
Explanation:

The differential lets left and right driven wheels rotate at different speeds during turns, preventing tyre scrubbing and easing steering.

9. Which tyre pressure condition may cause poor fuel economy and increased tyre wear on the edges?

Correct inflation
Slight over-inflation to manufacturer spec
Using higher-quality fuel
Under-inflation
Explanation:

Under-inflated tyres have higher rolling resistance (worse fuel economy) and excessive wear on tyre edges due to more flexing.

10. What is the main function of wheel balancing?

To distribute mass evenly around the wheel to prevent tyre vibration at speed
To change the tyre composition into a softer rubber
To make tyres sharper and cut through water better
To increase the tyre tread depth
Explanation:

Wheel balancing adds weights so the wheel-tyre assembly spins evenly, reducing vibration, wear and strain on suspension components.

11. Which material is commonly used for modern vehicle chassis frames because of its strength and lighter weight?

High strength steel and sometimes aluminium
Glass panels
Pure wood beams
Ceramic bricks
Explanation:

Modern chassis use high-strength steel and often aluminium to balance strength, stiffness and lower weight for better performance and efficiency.

12. What is the purpose of anti-roll (sway) bars in a vehicle's suspension?

To increase engine power during acceleration
To reduce brake fade during heavy braking
To reduce body roll during cornering by linking opposite wheels
To inflate tyres automatically
Explanation:

Anti-roll bars connect left and right suspension to resist body roll in turns, improving stability and handling.

13. Which part transfers torque from the gearbox to the differential in a rear-wheel drive car?

Timing belt
Driveshaft (propeller shaft)
Steering column
Fan belt
Explanation:

The driveshaft transmits engine torque from the gearbox to the rear differential in rear-wheel drive vehicles.

14. What is camber angle in wheel alignment?

The distance between the road and the bumper
The forward or backward angle of the steering wheel
The angle of headlight beam
The tilt of the wheel inward or outward when viewed from the front of the vehicle
Explanation:

Camber is the inward (negative) or outward (positive) tilt of a wheel and affects tyre contact and wear.

15. Which component supports the wheel and allows it to rotate smoothly on its axle?

Synchroniser
Wheel bearing
Distributor cap
Carburettor
Explanation:

Wheel bearings are mounted at the hub and allow the wheel to rotate with minimal friction while supporting load.

16. What is porpoising in a vehicle chassis context?

A type of fuel pump failure
A repeated bouncing motion of the vehicle usually at speed due to suspension issues
Loss of battery charge when the lights are on
Rust formation on the exhaust pipe
Explanation:

Porpoising describes oscillatory vertical motion caused by improperly damped suspension or improper setup at certain speeds.

17. Which maintenance practice helps prevent corrosion of the chassis in Kenya's rainy and coastal areas?

Using only premium unleaded petrol
Regular washing and application of anti-rust treatments
Adding sand to the fuel tank
Painting tyres with oil
Explanation:

Cleaning to remove salt, mud and grime and applying anti-rust coatings reduce corrosion risk, especially in wet or coastal climates.

18. What is caster angle and how does it affect steering?

The pressure needed to inflate the tyre
The tilt of the steering axis viewed from the side; it affects straight-line stability and steering return
The amount of tyre tread showing on the roadside edge
The spacing between bolts on the wheel rim
Explanation:

Caster is the forward or rearward tilt of the steering axis which influences stability and how the steering wheel returns to centre.

19. Which brake system component stores hydraulic pressure and helps maintain braking force in power-assisted brakes?

Alternator
Exhaust manifold
Oil pan
Brake master cylinder (and brake booster in power brakes)
Explanation:

The master cylinder creates hydraulic pressure and the booster (in power brakes) helps amplify pedal force for easier braking.

20. What does tyre tread depth affect most directly?

Brake fluid boiling point
Grip on wet roads and stopping distance
Engine oil viscosity
Battery charging rate
Explanation:

Adequate tread depth channels water away and maintains contact, improving wet grip and reducing stopping distance.

21. Which part is used to lift a vehicle safely when changing a wheel?

Radiator cap
Fuel filler cap
Jacking point and a suitable jack
Spare engine
Explanation:

Vehicles have designated jacking points to safely support lifting with a jack when changing tyres; using wrong points can damage the chassis.

22. What is the role of bushes (bushings) in suspension and steering linkages?

To increase tyre pressure automatically
To pump brake fluid through the lines
To cool down the engine oil
To provide flexible cushioning and reduce metal-to-metal contact
Explanation:

Bushes isolate vibration, allow controlled movement and reduce noise and wear where suspension and steering parts pivot.

23. Which type of axle is most likely used on heavy trucks to carry heavy loads and withstand rough roads?

Paperboard axle with rubber padding
Single-piece aluminium axle with coil springs
Solid (beam) axle with leaf springs
Carbon fibre hollow axle with air springs
Explanation:

Heavy trucks commonly use solid beam axles and leaf spring suspensions for strength, load capacity and durability on rough roads.

24. What is the effect of excessive toe-in or toe-out on tyres?

Cooler brake discs and longer brake life
Improved radio reception
Uneven and rapid tyre wear and poorer steering response
Better fuel economy and longer engine life
Explanation:

Incorrect toe causes tyres to scrub while rolling, leading to uneven wear and degraded handling.

25. Why is regular inspection of chassis mounting points and welds important?

To improve the colour of the paint on the roof
To increase tyre pressure automatically
To reduce engine compression slowly
To detect cracks, corrosion or looseness that could weaken vehicle structure
Explanation:

Checking mounts and welds finds structural problems early, preventing failures that could cause unsafe driving conditions.

26. Which system in the chassis helps support the weight of the vehicle and keeps the wheels in contact with the road?

Exhaust system
Suspension system
Ignition system
Fuel delivery system
Explanation:

The suspension supports vehicle weight, absorbs bumps and keeps tyres in contact with the road for control and comfort.