35.28. In which case is a passenger car more stable against overturning when cornering?
UAУ якому випадку легковий автомобіль більш стійкий проти перекидання на повороті?
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This is an exam question from the Ukrainian Traffic Rules about safety when driving through curves and the lateral stability of a vehicle. In real driving, a vehicle experiences lateral forces on a curve, which can lead to sideways skidding or even rollover if the driver does not take into account speed, road surface conditions, and the distribution of mass in the vehicle. That is why such topics often appear on the theoretical exam: they test not only memory but also understanding of how physics affects vehicle behavior.
In terms of content, this question is related to Section 12 "Speed of Movement" (item 12.1), where the traffic rules require drivers to consider the road situation and the characteristics of the cargo to maintain control of the vehicle, as well as Section 22 "Carriage of Cargo" (item 22.2), which directly prohibits placing cargo in a way that compromises the stability of the vehicle. The key principle here is simple: the lower the center of gravity, the smaller the overturning moment in a turn and the higher the resistance to rollover.
The explanation of the options comes down to the influence of passengers and cargo on the center of gravity. When the car is empty, its center of gravity is usually lower, so the margin of lateral stability is greater. Adding passengers raises the overall center of mass and worsens stability compared to an empty car. The worst for stability is when cargo is placed high, for example on a roof rack: then the center of gravity rises the most, and the risk of rollover at the same turn radius and speed increases. The practical conclusion for learning under the Ukrainian Traffic Rules: with cargo and passengers, turns should be taken more cautiously, and items on the roof require special attention to speed and maneuvers.
Clause 12.1 (Section 12 "Speed of movement")
When choosing a safe speed within the established limits, the driver must take into account the road situation, as well as the characteristics of the cargo being transported and the condition of the vehicle, in order to be able to constantly control its movement and drive it safely.
Brief application: the question about stability in a turn is related to the fact that the presence/absence of cargo and passengers changes the behavior (stability) of the car, and the Traffic Rules directly require taking into account the "characteristics of the cargo" when choosing a safe speed (especially in turns).
Clause 22.2 (Section 22 "Cargo transportation")
The cargo must be placed and secured in such a way that it does not create danger for other road users, does not limit the driver's visibility, does not complicate driving and does not violate the stability of the vehicle, does not block external lighting devices and reflectors, registration and identification plates, and also does not interfere with the perception of signals given by hand, does not create noise, does not raise dust, and does not pollute the roadway.
Brief application: The Traffic Rules directly state that the cargo must not "violate the stability of the vehicle"; therefore, any loading/passengers potentially worsen stability compared to an empty car, especially in a turn.
That is, the correct answer is "Without cargo and passengers.", given that according to the definition of the Traffic Rules, the driver must ensure such transportation (and consideration of cargo when choosing speed) that does not violate the stability of the vehicle, and an empty passenger car is the most stable in a turn.
When taking a turn, a lateral force acts on the car, which tries to "push" it outward from the curve. If this force creates too great an overturning moment, the car may lose lateral stability and start lifting its inner wheels, and in a critical situation — overturn.
The height of the center of gravity is crucial here. The lower the center of gravity is located, the shorter the "lever arm" through which the lateral force creates the overturning moment. Accordingly, it becomes harder for the car to "tip over" the edge of the track, and its lateral stability in the turn is higher.
When there are passengers in the cabin or the car is loaded with items, the total mass is distributed higher above the road level, and the center of gravity rises. This effect is even more noticeable if the load is placed high (for example, on a roof rack). In such a situation, on the same turn and at the same speed, the overturning moment becomes greater, and the stability margin — smaller.
Therefore, under identical conditions (turn radius, speed, road surface condition), the most stable car against overturning will be the one with the lowest center of gravity, that is, without additional mass from passengers and cargo.
Thus, the correct answer is "Without cargo and passengers," since an empty car has a lower center of gravity and a smaller overturning moment in a turn, which means higher stability against overturning.