What happens when the driver releases the brake pedal?

When the driver releases the brake pedal, the brake fluid from the hydraulic circuit returns to the reservoir. This action is part of the braking system's hydraulic principles, where applying the brake pedal increases pressure in the system, pressing the brake pads against the rotors to slow or stop the vehicle. When the pedal is released, the pressure is relieved, enabling the brake fluid to flow back to the reservoir. This return of fluid allows the brake pads to disengage from the rotor, thereby releasing the brakes and allowing the wheels to rotate freely once again.

This response highlights the essential mechanics of hydraulic braking systems and ensures that the driver can maintain control of the vehicle after braking.