Wyoming CDL — Air Brakes Practice Test 1

1.Which pairing of a pressure figure and what happens there matches Wyoming's Section 5?

About 100 psi: the low air warning comes onAbout 125 psi: the spring brakes come fully onUsually 150 psi: the safety relief valve opensAbout 60 psi: the governor cuts the compressor out

2.ABS is meant to prevent skids and jackknifes that braking sets off. Which kind of skid do the manual's ABS safety reminders say it will NOT prevent?

A skid from locking the steering wheels under hard brakingA trailer swing set off by overbrakingA jackknife caused by braking too hard on a wet roadA skid from spinning the drive wheels or taking a turn too fast

3.At the bottom of a long, steep hill you pull into a lot to park, and your brakes are still very hot. Which order of steps fits the manual?

Hold the vehicle with wheel chocks on level ground, let the brakes cool, then use the parking brakesSet the parking brakes right away, then chock the wheelsSet the parking brakes, then release them once the drums coolLeave the vehicle in gear without chocks until the brakes cool

4.If a driver ignores a low air warning, falling pressure will eventually bring the spring brakes on by themselves. Which pairing of vehicle and risk matches the manual?

Lightly loaded vehicle: no effect, because spring brakes need a full load to applyHeavily loaded vehicle: an abrupt stop, because its weight adds braking forceLightly loaded vehicle: a longer stop than a loaded one, because the springs apply slowlyHeavily loaded vehicle: a long stopping distance, because spring brakes do not act on every axle

5.Your dual-system truck fails the Step 7 air pressure buildup check, even measured against the manufacturer's specifications. What does the manual tell you to do?

Drive, but keep below 45 mphDrive, and watch the gauges closelyDrain the air tanks and then driveDo not drive until the problem is fixed

6.Wig-wag low air warnings come in an automatic type and a manual reset type. How do they differ once pressure is back above the warning level?

The automatic arm has to be pushed up by hand; the manual reset arm rises by itselfBoth arms stay down until the engine is shut offThe automatic arm rises out of view by itself; the manual reset arm has to be put out of view by handThe automatic arm sounds a buzzer; the manual reset arm lights a red lamp

7.Which part of an air brake system is an electric switch that air pressure operates?

The air compressor governorThe stop light switchThe safety relief valveThe alcohol evaporator

8.Which pairing of a part and its standard matches the Step 5 walk-around check in Section 5?

Air hoses to the brake chambers: not cut, and not worn from rubbingLinings: oil-soaked is acceptable if they are still thickMechanical parts: one missing part per axle is acceptableDrums or discs: cracks are acceptable up to the full width of the friction area

9.Wyoming's manual lists situations in which a written test and a commercial learner's permit (CLP) are required. Which of these is on that list?

Removing the air brake restriction "L" from a CDLRenewing a Wyoming CDL that has not expiredReporting a new home address to the departmentCanceling a skills test appointment

10.Which of these is NOT part of a normal stop as Section 5 describes it?

Pushing the brake pedal downControlling the pressure so the stop is smooth and safePulling the parking brake knob out as the vehicle slowsSelecting a starting gear once the vehicle has stopped