When **speed increases**, the **reaction distance** also increases. This means that the time it takes for a driver to perceive a hazard and begin to react is longer, resulting in a greater distance covered before the driver can act.

- **Reacting to unforeseen events** becomes more difficult at high speeds. This is because the driver needs more time and space to process information and make appropriate decisions.

- **Tunnel vision** is an effect that occurs at high speeds, where the driver can only focus on what is directly in front of them, reducing their ability to detect hazards on the sides. This also contributes to a greater reaction distance, as the driver may not notice a hazard until it is very close.

- Maintaining an **appropriate speed** is crucial to effectively control the vehicle in unexpected situations. Excessive speed reduces this control ability and increases the risk of serious accidents.

In summary, as speed increases, the reaction distance increases, which can lead to dangerous situations if the vehicle is not properly controlled.