Welcome to the Air Brake Quiz 1. The main purpose of the hand valve is to:Act as an emergency brake if the foot valve failsControl the amount of application air directed to the tractor brakesControl the amount of application air directed to the trailer brakesSupplement the other braking system2. The weight of a vehicle is doubled. To stop in the same distance, the braking power must be increased:8 times2 times4 times6 times3. Reservoirs should be drained at least:DailyMonthlyWeeklyBi-weekly4. The 20 lb range between the cut-in and cut-out of the governor serves to:Give the system a pressure variationCool the compressorRemove impurities from the linesReduce condensation in the wet tank5. A tug test on the trailer brakes should be done with the:Foot valve appliedParking brake and hand valve appliedHand valve appliedParking brake applied6. In a 105 PSI system, the governor will cause the compressor to return to its pumping stage at a pressure of:65 PSI85 PSI105 PSI95 PSI7. The low pressure warning device activates at:50 PSI40 PSI60 PSI85 PSI8. When necessary, a driver should use the manual front wheel limiting valve on slippery roads:To reduce the brake application pressure by 50 percentInstead of the hand valveTo reduce the brake application by 25 percentTo cut out the front wheel brakes9. If your brakes do not seem to be holding even when air pressure is sufficient, you should:Report the condition at the end of the tripTravel at a reduced speedContinue normally, as long as you have some braking powerStop, check the brakes and make adjustments10. Why should you lock the tractor glad hands to each other, or use dummy couplers when you are NOT towing a trailer?If you did not, you could never build up system pressureIt saves wear on the compressorThe brake circuit becomes a back-up air tankIt keeps dirt and water out of the lines11. To stop a vehicle, the energy of motion is turned into:FrictionTractionHeat in the brake lining and drumsMoisture in the reservoirs12. When the foot and hand valve are operated at maximum at the same time, the application pressure will:Be less than the reservoir pressureBe greater than reservoir pressureCompound the force exerted on the brake chambersBe the same as the reservoir pressure13. The foot valve:Automatically adjusts to braking requirementsNeeds reservoir pressure to control it to within 10 PSIContinuously maintain applied pressure when in useShould be used instead of the hand valve14. In a dual circuit air system, the valve that protects the primary circuit from air loss in the secondary circuit is the:Two-way check valveDual circuit foot valveEmergency relay valveLimiting valve15. When a trailer without spring parking brakes is disconnected and left parked, you should make sure:The brakes are properly adjustedThe trailer is dynamitedThe wheels are blockedThe air lines are sealed16. The final factor in determining if a vehicle will move is the amount of:FrictionTractionPowerInertia17. Responsibility for ensuring that the braking system is operational finally rests with the:Company or ownerDriverCompany mechanicMaintenance crew18. In a dual circuit air system, air from the primary and secondary air reservoirs is directed to:The relay valveThe front wheel limiting valveThe one-way check valveThe foot valve19. If the brakes are out of adjustment, the force of the spring brakes when applied will be:GreaterVariableLessThe same20. When a compressor discharge line is broken, total loss of air is prevented by the:Governor valveOne-way check valveTwo-way check valveRelay valve Your Name Time is Up!