New Jersey Air Brakes Practice Test

What is the role of the emergency brake?

1. To increase acceleration in emergencies

2. To hold the vehicle stationary when parked

3. To assist in normal braking

4. To prevent the vehicle from rolling backward

The correct answer is: To hold the vehicle stationary when parked

The emergency brake, also known as the parking brake, plays a crucial role in ensuring vehicle safety, especially when the vehicle is stationary. Its primary function is to keep the vehicle secure and prevent it from rolling away when parked. This is particularly important on inclines or uneven surfaces where gravity could cause the vehicle to move unexpectedly. While assisting in normal braking can be an additional function in some systems, the core purpose of the emergency brake is to provide a reliable means of immobilizing the vehicle, which is why option B is the correct answer. The other options suggest functions that do not align with the primary safety purpose of the emergency brake. For instance, the emergency brake does not enhance acceleration, and while it may help prevent backward rolling in some contexts, its main focus is on securing the vehicle when parked, rather than assisting in its movement or regular braking functions.