How is the brake cylinder operated in the air brake system?

Answer: C — By the application of compressed air, which forces the piston to move

The brake cylinder in an air brake system operates through the application of compressed air, which forces the piston to move. When the engineer initiates a braking action, air from the main reservoir is directed into the brake cylinder. This pressurized air pushes against the piston within the cylinder, creating the necessary force to engage the brake shoes against the wheels. This method is efficient and allows for rapid response times, enabling the train to decelerate effectively while maintaining control. Since the operation relies on pneumatic principles rather than hydraulic fluid or manual interaction, it ensures that the brake system can operate consistently across various conditions and does not rely on gravitational forces. The design of air brake systems optimizes safety and reliability, making compressed air the primary means of actuation.