What additional safety device must be fitted to a trailer braking system?

Final answer: An important safety device required for trailer braking systems is a breakaway system, which activates the trailer's brakes if it detaches from the towing vehicle. This, along with other safety features in vehicles, highlights the significance of proper safety measures to minimize driving risks. Explanation: When considering the safety of trailer braking systems, an additional device that is often required is a breakaway system. This safety feature is designed to activate the trailer's brakes in the event that the trailer becomes disconnected from the towing vehicle. The system typically includes a battery that provides the necessary power and a switch that is triggered when the trailer detaches. This ensures that the trailer will come to a stop, even if it is no longer attached to the tow vehicle, thereby preventing potential accidents or damage. In the context of overall vehicle safety, it is essential to understand various aspects related to stopping distances, such as the distance a driver covers before hitting the brakes and the total distance needed to bring the vehicle to a complete stop. Additionally, safety features in vehicles, including seat belts, airbags, and anti-lock brakes, play pivotal roles in minimizing the risks associated with driving. Electrical safety systems and devices, such as circuit breakers and the three-wire system, provide relevant context by illustrating the importance of adequate safety measures to prevent hazards, analogous to the necessity of having effective safety devices in trailer braking systems.