AIR BRAKES PRACTICE TEST - LOUISIANA
21.
Why must air tanks be drained?
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Water can freeze in cold weather and cause brake failure.
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Water and
oil reduce the air pressure.
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To keep from fouling the air compressor oil.
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The low boiling point of water reduces braking power.
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22.
With a fully-charged air system, the leakage rates should be less than:
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5 psi for single vehicles and 10 psi for a combination of two vehicles.
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5 psi for single vehicles and 4 psi for a combination of two vehicles.
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2 psi for single vehicles and 3 psi for a combination of two vehicles.
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3 psi for single vehicles and 4 psi for a combination of two vehicles.
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23.
Which of the following is NOT a warning sign of fatigue?
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Trouble remembering the last few miles driven
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Heavy eyelids
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Frequent blinking
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Driving at the speed of the traffic
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24.
The air compressor governor:
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allows the compressor to start pumping air when the tank pressure rises to the "cut-out" pressure.
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controls when the air storage tanks will pump air into the air compressor.
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stops the compressor from pumping air.
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All of the above.
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25.
The one-way check valve:
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keeps your wheels from locking up when you brake hard.
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supplies air to the trailer air tanks.
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keeps the axles in place.
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keeps air from going out if the air compressor develops a leak.
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