1. What is the final factor that will determine if the vehicle will move?
2. What is the final factor that will determine if the vehicle will stop?
3. How is the heat dissipated that is generated by the brakes?
4. If one set of brake shoes are poorly adjusted, what effect could it have on the remaining sets of brake shoes in the system?
5. What is meant by the term ‘FRICTION’?
6. If the weight of the vehicle is doubled, how many times must the stopping power be increased?
7. If both weight and speed of the vehicle are doubled, how many times must the stopping power be increased to be able to stop in the same distance?
8. If the speed of the vehicle is doubled, how many times must the stopping power be increased to be able to stop in the same distance?
9. What is compressed air?
10. What does the abbreviation ‘P.S.I.’ stand for?
11. If 40 P.S.I. is exerted against a diaphragm of 30 square inches in area, what is the total pounds of force that could be exerted?
12. ‘Brake lag’ is approximately 4/10 of a second in a well maintained, single circuit brake system. What is meant by ‘brake lag’?
13. What is meant by the following terms? ‘reaction distance’ – ‘braking distance’ – ‘stopping distance’.

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Section 1 of this manual has explained that it is possible to gain a mechanical advantage through the use of levers and that air under pressure can be used to gain a mechanical advantage. Section II will explain how air under pressure can be used to operate the air brakes of a vehicle.

Piping diagrams have been kept simple in order to be easily understood. The piping arrangements found on vehicles in actual use on the highway might differ somewhat from the illustrations in this manual.

The diagrams in this manual ARE NOT to be interpreted as regulations for, or specifications of, air brake systems.