Final answer:
Using a horn when a truck is in motion at intersections or blind spots is an important safety practice, contrary to the belief that it's unnecessary. It alerts other road users and helps prevent accidents, especially in areas where vehicles tend to speed or there are vulnerable road users present.
Step-by-step explanation:
It is often a misconception that when a truck is in motion, it is not necessary to sound the horn at intersections and blind spots. In reality, using your horn in these situations can be an important safety measure. It alerts other road users, including pedestrians, that a large vehicle is approaching, which is critical given that trucks have larger blind spots and require more time to stop than smaller vehicles.
For example, vehicles that speed through the intersection without heed to the posted speed limits could create hazardous situations. Installing a traffic signal at such intersections encourages drivers to slow down and reduces the likelihood of accidents. In scenarios where a child is a certain distance ahead, such as 50 meters, preemptively using the horn can alert the child to the presence of the truck, increasing safety.
Therefore, while it might not be mandatory in all locations or situations to use the horn, it is certainly a best practice to do so when driving through intersections or blind spots to prevent accidents and ensure the safety of all road users.