Air Brakes CDL (maryland)

48 Questions

Settings
Please wait...
Air Brakes CDL (maryland)

.


Related Topics
Questions and Answers
  • 1. 
    Air Brakes are compossed of two different braking systems.
    • A. 

      True

    • B. 

      False

  • 2. 
    The v-belt controls when the air compressor will pump air into the air storage tanks.
    • A. 

      True

    • B. 

      False

  • 3. 
    Water can freeze in cold weather and cause brake failure.
    • A. 

      True

    • B. 

      False

  • 4. 
    To reduce the risk of ice in air brake valves, the alcohol evaporator removes alcohol from the air system.
    • A. 

      True

    • B. 

      False

  • 5. 
    The safety valve is usually set to open at 150 psi.
    • A. 

      True

    • B. 

      False

  • 6. 
    The s-cam forces the brake shoes away from one another and away from the inside of the drums.
    • A. 

      True

    • B. 

      False

  • 7. 
    Increasing application pressure to hold the same speed means the brakes are not fading.
    • A. 

      True

    • B. 

      False

  • 8. 
    A warning signal must come on before the air pressure in the tanks falls below 75 psi.
    • A. 

      True

    • B. 

      False

  • 9. 
    Parking brakes must be held on by mechanical force.
    • A. 

      True

    • B. 

      False

  • 10. 
    If the air pressure is removed, the brakes cannot be put on.
    • A. 

      True

    • B. 

      False

  • 11. 
    Tractor and straight truck spring brakes will come fully on when air pressure drops to a range of 20 to 45 psi.
    • A. 

      True

    • B. 

      False

  • 12. 
    If the brakes are not adjusted properly, the regular brakes will not work right but the emergency/parking brakes will work right.
    • A. 

      True

    • B. 

      False

  • 13. 
    When main air pressure is lost, the spring brakes come on.
    • A. 

      True

    • B. 

      False

  • 14. 
    Before driving a vehicle with a dual air system, allow time for the air compressor to build up to a minimum of how much pressure in the primary and secondary systems?
    • A. 

      30 psi

    • B. 

      100 psi

    • C. 

      50 psi

    • D. 

      125 psi

  • 15. 
    To test the low pressure warning signal, shut the engine off when you have enough air pressure so that the low pressure warning signal is not on.  Then keep pumping the brake pedal until the low pressure warning comes on. 
    • A. 

      True

    • B. 

      False

  • 16. 
    When the engine is at operating rpms, the pressure whould build from 85 to 100 psi within how many seconds in dual air systems?
    • A. 

      35 seconds

    • B. 

      15 seconds

    • C. 

      60 seconds

    • D. 

      45 seconds

  • 17. 
    Pumping by the air compressor should start at about:
    • A. 

      100 psi

    • B. 

      125 psi

    • C. 

      150 psi

    • D. 

      200 psi

  • 18. 
    In an emergency stop, you should brake in a way that will turn the vehicle.
    • A. 

      True

    • B. 

      False

  • 19. 
    Perception Distance + Brake Lag Distance = Total Stopping Distance
    • A. 

      True

    • B. 

      False

  • 20. 
    The air brake lag distance at 55 mph on dry pavement adds about:
    • A. 

      12 feet

    • B. 

      22 feet

    • C. 

      32 feet

    • D. 

      42 feet

  • 21. 
    Brakes can fade or fail from excessive heat.
    • A. 

      True

    • B. 

      False

  • 22. 
    The use of brakes on a long and/or steep downgrade is more important than the braking effect of the engine.
    • A. 

      True

    • B. 

      False

  • 23. 
    Release the brakes when your speed has been reduced to approximately how much below your "safe" speed?
    • A. 

      5 mph

    • B. 

      7 mph

    • C. 

      10 mph

  • 24. 
    A heavily loaded vehicle will take a short distance to stop.
    • A. 

      True

    • B. 

      False

  • 25. 
    When driving down a long steep hill you should use a low gear and...
    • A. 

      Use stab braking

    • B. 

      Begin braking when you are 5 mph above your "safe" speed

    • C. 

      Go slow enough that a fairly light, steady use of the brakes will keep you from speeding up...

    • D. 

      Use the trailer brakes

  • 26. 
    Your brakes are fading when...
    • A. 

      Less than half the brake lining remains

    • B. 

      The brake pedal feels spongy when you apply pressure

    • C. 

      You release pressure on the brake pedal and your speed increases

    • D. 

      You have to push harder on the brake pedal to control your speed on a downgrade

  • 27. 
    A combination vehicle (tractor-trailer) air brake system cannot leak more than __ psi per minute with the engine off and the brakes released.
    • A. 

      1

    • B. 

      2

    • C. 

      3

    • D. 

      4

  • 28. 
    A straight truck or bus (single vehicle) air brake system cannot leak more than __ psi per minute with the engine off and the brakes released.
    • A. 

      1

    • B. 

      2

    • C. 

      3

    • D. 

      4

  • 29. 
    The extra time that it takes for air brakes to work when compared with hydraulic brakes is due to the time it takes for air to flow through the lines. This is called...
    • A. 

      Brake lag

    • B. 

      Perception time

    • C. 

      Reaction distance

    • D. 

      None of the above

  • 30. 
    At what psi will the spring brakes come fully on?
  • 31. 
    When should the air compressor stop pumping air?
  • 32. 
    When should the air compressor start pumping air?
  • 33. 
    How long should the pressure take to build up from 85 - 100 psi in dual air systems?
  • 34. 
    You have to make an emergency stop, how should you brake?
    • A. 

      In a way that will keep the vechile in a straight line and allow you to stop safe quickly.

    • B. 

      In a way that will keep your vehicle in a straight line and allow you to turn if it becomes necessary.

    • C. 

      As hard as you can to stop the fastest without locking the wheels.

    • D. 

      As hard as you can, without knocking anything down that is in the cab.

  • 35. 
    What equals Total Stopping Distance
    • A. 

      Perception Distance + Reaction Distance + Brake Lag Distance

    • B. 

      Perception Distance + Reaction Distance + Brake Lag Distance + Stopping Distance

    • C. 

      Perception Distance + Reaction Distance + Brake Lag Distance + Effective Stopping Distance

    • D. 

      Perception Distance + Reaction Distance + Effective Stopping Distance

    • E. 

      Done of The Above

  • 36. 
    What does brakes shoes or pad rub against to slow the vehicle?
  • 37. 
    When you are coming down a steep hill what gear should you be in?
    • A. 

      The lowest gear possible

    • B. 

      A gear lower then the one you would be in going up the hill

    • C. 

      Stay in the gear you started in

    • D. 

      Go down by one gear

  • 38. 
    The govenor controls how much pressure is put into the tanks
    • A. 

      True

    • B. 

      False

  • 39. 
    The "cut-out" level for the govenor to stop pumping air is at how many psi?
    • A. 

      85

    • B. 

      100

    • C. 

      125

  • 40. 
    The "cut-in" level for when the govenor starts pumping air is how many psi?
    • A. 

      100

    • B. 

      85

    • C. 

      125

  • 41. 
    The service brake is for naormal braking
    • A. 

      True

    • B. 

      False

  • 42. 
    At what psi will the safety valve open signaling there is a problem?
    • A. 

      150

    • B. 

      200

    • C. 

      125

    • D. 

      175

  • 43. 
    An air pressure warning you can see will come on
    • A. 

      Before air pressure in the tanks fall below 60 psi

    • B. 

      After air pressure in the tanks falls below 60 psi

    • C. 

      Whan more than 2 psi has leaked

  • 44. 
    Tractor and straight truck spring brakes will come fully on when air pressure drops to a range of
    • A. 

      50 to 75 psi

    • B. 

      20 to 45 psi

  • 45. 
    Some vehicles may have dual air tanks so you can move the vehicle in an emergency
    • A. 

      True

    • B. 

      False

  • 46. 
    At 55 mph the average driver has how many feet  stopping distance?
  • 47. 
    The parking brake must always be used when parked
    • A. 

      True

    • B. 

      False

  • 48. 
    How often should you drain air tanks?
    • A. 

      Pre trip

    • B. 

      Post trip

    • C. 

      Both before and after a trip