When friction brake trips, what is one of the consequences?

When the friction brake trips, one significant consequence is that no friction brake will engage on the affected car. This situation arises because the trip mechanism acts as a safety feature to prevent the brake system from operating under potentially unsafe conditions. For a railway or transportation system, the involved car losing the ability to engage its friction brakes can lead to increased stopping distances and reduced control, making it essential to ensure the physical brake mechanism operates correctly and reliably.

The design of modern brake systems often includes fail-safe features. If a fault is detected in the friction brakes, the system may automatically trip, effectively disengaging any further attempts to engage those brakes until the issue is resolved. This design helps prevent uncontrolled movements or unsafe operation.

The other potential options don’t directly relate to the immediate impact of a friction brake tripping. For example, passenger lights turning on, the failure of all dynamic brakes, and emergency exit doors unlocking do not occur as direct consequences of the friction brake system's malfunction. In summary, understanding that no friction brake engagement happens emphasizes the importance of maintaining and monitoring the braking system's functionality for safety in transportation contexts.