CAE Vehicle Dynamics & Powertrain 3

Question 1

What is the primary advantage of a continuously variable transmission (CVT) over a conventional stepped automatic?

Accepted Answer

Ability to keep the engine at its most efficient RPM across a range of vehicle speeds

Answer

A CVT uses a continuously adjustable ratio to hold the engine in its peak efficiency band regardless of vehicle speed, improving overall fuel economy.

Question 2

How does increasing front anti-roll bar stiffness affect vehicle handling balance?

Accepted Answer

Increases understeer tendency by increasing front lateral load transfer

Answer

A stiffer front anti-roll bar transfers more lateral load to the outer front tire, reducing front cornering grip and promoting understeer.

Question 3

In a dual-clutch transmission (DCT), how are odd and even gear ratios typically organized?

Accepted Answer

Odd gears on the outer clutch pack, even gears on the inner clutch pack with separate input shafts

Answer

A DCT has two concentric input shafts — one for odd gears and one for even gears — each with its own clutch, enabling pre-selection and near-instantaneous shifts.

Question 4

What is 'camber thrust' in tire mechanics?

Accepted Answer

The lateral force a tire generates due to camber angle, independent of slip angle

Answer

Camber thrust is a lateral force produced by a tilted tire trying to roll in a circle, adding to or subtracting from cornering force depending on camber direction.

Question 5

Which condition does a vehicle's 'scrub radius' most directly influence?

Accepted Answer

Steering feel and torque steer sensitivity under braking or acceleration

Answer

Scrub radius is the offset between the steering axis and the tire contact patch center; a large scrub radius amplifies drivetrain and braking forces into the steering column.

(CAE) Certified Automotive Engineer Practice Test

(CAE) Certified Automotive Engineer Practice Test

CAE Vehicle Dynamics & Powertrain 3