What factor can significantly affect the stopping distance of a combination vehicle?

The weight of the cargo is a crucial factor that can significantly affect the stopping distance of a combination vehicle. Heavier loads increase the momentum of the vehicle, meaning that more force is required to bring it to a stop. When a combination vehicle is fully loaded, it has a greater mass, which results in a longer stopping distance compared to when it is lightly loaded or empty. This is due to the physics principle that states that the stopping distance increases with the weight of the vehicle; therefore, extra caution is needed when braking to ensure that the vehicle can stop safely and effectively.

While aspects such as brake temperature, trailer height, and road surface do play a role in vehicle handling and braking performance, they are not as directly correlated to the fundamental principle of momentum as the weight of the cargo. For example, while brake temperature may affect braking efficiency, it is primarily the cargo weight that fundamentally alters the inertia of the vehicle and directly influences how much distance is required to stop safely.