SOS MECHANIC CERTIFICATION - BRAKES EXAM QUESTIONS WITH VERIFIED ANSWERS

SOS MECHANIC CERTIFICATION -
BRAKES EXAM QUESTIONS WITH
VERIFIED ANSWERS



1. What is the primary purpose of the brake booster in a hydraulic braking system?

A. To increase the fluid pressure in the brake lines.


B. To cool down the brake rotors and pads.


C. To prevent the wheels from locking up during emergency stops.


D. To amplify the force applied by the driver to the brake pedal.


Answer: D


Conceptual Explanation: The brake booster uses engine vacuum or hydraulic pressure to

assist the driver, thereby amplifying the force applied to the master cylinder.


2. Which component directly presses the brake pads against the rotor in a disc brake system?

A. Master cylinder


B. Caliper piston


C. Brake booster


D. Proportioning valve

, Answer: B


Conceptual Explanation: Hydraulic pressure forces the caliper piston outward, which

pushes the brake pads against the rotating disc rotor to slow the vehicle.


3. What type of brake fluid is most commonly used in modern automotive braking systems?

A. Silicone-based DOT 5


B. Mineral oil-based fluid


C. DOT 3


D. Transmission fluid


Answer: C


Conceptual Explanation: DOT 3 (along with DOT 4) is a glycol-based brake fluid widely

used in most standard automotive braking systems.


4. What is the main function of the proportioning valve in a braking system?

A. To balance hydraulic pressure between the front and rear brakes during a stop.


B. To bleed air out of the hydraulic lines automatically.


C. To activate the brake warning light when fluid is low.


D. To store reserve vacuum for the brake booster.


Answer: A