35.92. Is it necessary to reduce speed in this case?
UAЧи потрібно у даному випадку зменшити швидкість?
This exam question from the Traffic Rules of Ukraine tests a basic safe driving skill: the ability to adjust speed according to actual road conditions. In fog, twilight, rain, or snowfall, the driver sees less and therefore has less time to react and brake, so the correct choice of speed directly affects the risk of an accident.
In terms of content, it belongs to the section of the Traffic Rules about speed and safe speed (points 12.1–12.2), and is also related to the term "insufficient visibility" (point 1.10). The logic is simple: at night and in conditions of insufficient visibility, the speed must be such that the driver can stop the vehicle within the visible section of the road. Therefore, the option "necessary" is the only correct one for the theoretical exam: the permitted speed or the speed of the traffic flow does not cancel the requirement to choose a safe one.
Incorrect options like "not necessary" and "not necessary if those ahead do not slow down" contradict the Traffic Rules: every driver is responsible for their own speed and must ensure the ability to stop within the visible range, regardless of the behavior of others. In practice, this means: reduce speed, increase following distance, and be ready for a sudden obstacle ahead, which in fog may be noticed too late.
Clause 12.2
At night and in conditions of insufficient visibility, the driving speed must be such that the driver is able to stop the vehicle within the visible distance of the road.
Clause 12.1
When choosing a safe driving speed within the established limits, the driver must take into account the road situation, 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.
Clause 1.10 (term "Insufficient visibility")
Insufficient visibility — road visibility of less than 300 m at dusk, in conditions of fog, rain, snowfall, etc.
Clause 1.10 (term "Night time")
Night time — the part of the day from sunset to sunrise.
That is, the correct answer is "It is necessary.", given that according to the requirements of the Traffic Rules (clause 12.2), in conditions of insufficient visibility, the speed must ensure the possibility of stopping within the visible distance of the road, therefore it should be reduced.
In the situation shown, the driving conditions are characterized by insufficient visibility: due to fog (or similar weather phenomena), the road ahead can be seen only for a limited distance. This means that the driver notices an obstacle, a change in the situation, or a stopped vehicle later.
According to clause 12.2 of the Traffic Rules of Ukraine, at night and in conditions of insufficient visibility, the speed must be chosen so that the driver can stop the vehicle within the distance that is actually visible ahead. That is, the speed should depend not on the permitted values for this road, but on the actual visibility at the moment.
Practically, this means: if only a short section of the road is visible in the fog and the car is moving too fast, then even with an immediate reaction, the braking distance may be longer than the visible distance. In this case, the driver physically will not have time to stop before an obstacle that is noticed too late. To avoid this, the speed must be reduced to a safe level.
Therefore, the correct answer is "It is necessary," because in conditions of insufficient visibility, according to clause 12.2, the speed must ensure the possibility of stopping within the section of the road visible to the driver.