35.19. How does a driver perceive the speed of their vehicle after prolonged driving on a flat road at high speed?
UAЯк сприймається водієм швидкість його автомобіля у випадку тривалого руху рівнинною дорогою з великою швидкістю?
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This is an exam question from the Traffic Rules of Ukraine (PDR) concerning the safety of high-speed driving and how human psychophysiology affects vehicle control. For a driver, it is important not only to know the permitted limits but also to understand that the sense of speed can be deceptive, especially on a flat, straight road during prolonged driving. Such a perception error directly increases the risk of speeding, lengthens the braking distance, and makes it harder to control the car, which contradicts the basic principles of traffic regulations.
The question tests the section of the PDR about speed and the driver’s duties regarding attentiveness and constant control of the vehicle (in particular, the requirements of point 12.1, as well as the general duty to be attentive under point 2.3). In the theoretical exam, it is important to recognize a typical situation: during monotonous driving at high speed, visual landmarks appear to move relatively slower (objects are far away, their angular displacement speed is lower), combined with adaptation and the comfort of the cabin, and the driver starts to feel as if they are driving slower than they actually are. That is why the option about underestimated perception of speed is logical and corresponds to real driver behavior in such conditions.
The other options do not take this adaptation effect into account: the statement that speed "seems higher" is more characteristic of situations with close visual landmarks (narrow road, dense buildings, trees close to the roadside), not for a long, flat, straight road. The option about unchanged perception ignores fatigue, monotony, and "getting used to" the high pace, due to which the driver may mistakenly increase speed and create danger, which contradicts the general requirement of the PDR of Ukraine not to create obstacles and threats to other road users (point 1.5). In practice, this knowledge means a simple rule: after prolonged high-speed driving, do not rely on your feelings, but consciously monitor the speedometer readings and ensure the speed matches the road conditions.
Clause 12.1
When choosing a safe driving speed within the established limits, the driver must take into account the road conditions, 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 checks the understanding that the subjective “sense of speed” can be misleading, so the driver must consciously control the speed and not rely solely on their own perception after prolonged driving at high speed.
Clause 2.3 (subclause b)
To ensure road safety, the driver is obliged to: be attentive, monitor the road situation, respond appropriately to its changes, monitor the correct placement and securing of cargo, the technical condition of the vehicle, and not be distracted from driving this vehicle on the road.
Brief application: prolonged monotonous driving and “getting used” to high speed reduce attentiveness and the accuracy of speed assessment, so the Traffic Rules directly require maintaining attentiveness and responding to changing conditions.
Clause 1.5
The actions or inaction of road users and other persons must not create danger or obstacles to traffic, threaten the life or health of citizens, or cause material damage.
Brief application: underestimating speed after prolonged driving can lead to exceeding the safe/allowed speed and creating danger, which the Traffic Rules do not allow.
That is, the correct answer is “It seems less than it actually is,” given that according to the requirements of the Traffic Rules, the driver is obliged to constantly control the speed and be attentive, since the subjective perception of speed may decrease during prolonged driving at high speed.
During prolonged driving on a flat, straight road at high speed, the driver's perception gradually "adapts." The road is monotonous, the steering wheel requires almost no corrections, and the surrounding scenery changes slowly and without sudden events. Because of this, the brain receives fewer external signals that are usually used to assess the pace of movement.
The driver perceives speed mainly visually: by how quickly the road surface "runs by" and how objects in the field of view shift relative to the car. On a flat section at high speed, typical reference points (trees, poles, signs, other cars) often remain far ahead or to the side at a significant distance for a long time. As a result, their noticeable movement to the eye becomes less, creating a false impression that the car is moving slower than it actually is.
Additionally, the comfort of a modern car and monotony have an effect: noise, vibrations, and other "clues" to speed are felt less, and attention becomes dulled. That is why after a long period of driving at high speed, the driver may underestimate the actual speed and unconsciously exceed the safe or permitted limit if they do not monitor the instrument readings.
Therefore, the correct answer is "It seems less than it actually is," because during prolonged high-speed driving on a flat, straight road, the number of visual reference points decreases and the sense of movement tempo is dulled, causing the actual speed to be perceived as lower.