What is the reaction of brakes on PA4s if the electric brake was cut out?

In the context of PA4 trains, if the electric brake system is cut out, the air brakes will function differently compared to when the electric brakes are engaged. The correct answer indicates that the brakes will have a slow applying and slow releasing characteristic. This is consistent with how pneumatic brakes operate when relying solely on air pressure.

When the electric brake is cut out, the system relies on the air brakes, which typically take more time to build up pressure and to apply force compared to the quicker response of electric systems. The "slow applying" nature means that the brake application will take longer to reach full braking force, allowing for a more gradual deceleration, which is important for maintaining comfort and safety for passengers. Similarly, the "slow releasing" aspect means that it takes some time for the brakes to fully disengage after the operator signals the release, preventing sudden jolts that could be caused by immediate disengagement.

In contrast, the other options do not accurately represent the behavior of air brakes when electric assistance is not available. Fast applications or immediate engagements could lead to abrupt stops, which is not typical for systems relying solely on air pressure, making these descriptions less safe and appropriate in this context. Regular application and quick releasing also fail to correctly describe the