Alabama CDL General Knowledge Practice Test # 3 — Questions and Answers

Question 1: HOW FAR AHEAD SHOULD YOU LOOK WHEN DRIVING?

10 to 12 seconds
8 to 10 seconds
12 to 15 seconds (Correct answer)
15 - 17 seconds

Correct answer: 12 to 15 seconds

Professional drivers of Commercial Motor Vehicles (CMVs) are taught to look 12 to 15 seconds ahead of their vehicle. This provides enough time to identify potential hazards, anticipate traffic changes, and react safely. At highway speeds, 12-15 seconds translates to approximately a quarter-mile, allowing for ample decision-making and maneuvering time.

Question 2: WHAT IS "BLACK ICE"?

Very hot slippery tar
Oil slick on the roadway
Snow on the roadway
Thin sheet of clear ice on roadway (Correct answer)

Correct answer: Thin sheet of clear ice on roadway

Black ice is a thin, transparent layer of ice that forms on the road surface, often appearing as wet pavement rather than obvious ice. Because it's clear, it's extremely difficult for drivers to see, making it particularly dangerous. It typically forms when temperatures are at or near freezing and moisture is present, creating a highly slippery and unexpected hazard.

Question 3: WHAT IS THE MOST IMPORTANT REASON FOR DOING A VEHICLE INSPECTION?

State law requires vehicle inspections
Safety is the most important reason to inspect your vehicle (Correct answer)
To make sure your lights are working properly
To check for over inflated tires

Correct answer: Safety is the most important reason to inspect your vehicle

While vehicle inspections are legally required and help prevent breakdowns, the paramount reason for conducting a thorough pre-trip inspection is safety. Identifying and addressing potential mechanical issues before starting a trip significantly reduces the risk of accidents, protecting the driver, other road users, and the cargo. A safe vehicle is a reliable vehicle.

Question 4: YOU CAN SAFELY REMOVE THE RADIATOR CAP AS LONG AS THE ENGINE ISN'T OVERHEATED.

TRUE
FALSE (Correct answer)

Correct answer: FALSE

It is never safe to remove a radiator cap when the engine is hot, even if it's not "overheated." The cooling system operates under pressure, and removing the cap while hot can cause superheated coolant and steam to erupt violently. This can result in severe burns. Always wait until the engine has completely cooled down before attempting to remove the radiator cap.

Question 5: IF YOU GO TWICE AS FAST, YOUR STOPPING DISTANCE WILL INCREASE BY TWICE OR 4 TIMES?

Twice
Four times (Correct answer)

Correct answer: Four times

Stopping distance increases exponentially with speed, not linearly. If you double your speed, your braking distance (the distance traveled after applying brakes) increases by a factor of four. This is because kinetic energy, which must be dissipated to stop the vehicle, is proportional to the square of the speed (E = 0.5 * m * v^2). Therefore, going twice as fast means four times the energy to dissipate, leading to four times the braking distance.

Question 6: WHAT DOES "COMMUNICATING" MEAN IN SAFE DRIVING?

Using cell phones
Braking often
Using your horn
Signaling your intentions (Correct answer)

Correct answer: Signaling your intentions

In safe driving, "communicating" primarily refers to making your intentions clear to other road users. This includes using turn signals, brake lights, hazard lights, and even eye contact or horn when necessary. Clearly signaling your intentions allows other drivers to anticipate your actions and react accordingly, which is crucial for preventing collisions and maintaining smooth traffic flow.

Question 7: WHAT SHOULD YOU DO BEFORE YOU DRIVE IF YOU ARE DROWSY?

Eat
Sleep (Correct answer)
Drink coffee
Exercise

Correct answer: Sleep

Drowsiness significantly impairs a driver's judgment, reaction time, and ability to stay alert, making it extremely dangerous to operate a Commercial Motor Vehicle (CMV). The most effective and safest remedy for drowsiness is to pull over to a safe location and get adequate sleep. Other temporary measures like coffee or exercise do not address the underlying fatigue and are not reliable long-term solutions.

Question 8: WHY SHOULD YOU BE IN PROPER GEAR BEFORE STARTING DOWN A HILL?

So you can focus on braking
You will not be able to shift into a lower gear once you are going down the hill (Correct answer)
To maintain speed
So you will not damage the transmission

Correct answer: You will not be able to shift into a lower gear once you are going down the hill

It is crucial to select the proper low gear before starting down a steep hill. Once the vehicle gains speed on a downgrade, it becomes very difficult, if not impossible, to shift into a lower gear without damaging the transmission or losing control. Being in the correct gear allows the engine to provide effective engine braking, helping to control speed and prevent the service brakes from overheating.

Question 9: WHERE SHOULD YOUR REFLECTORS BE PLACED WHEN STOPPED ON A DIVIDED HIGHWAY?

50'/50'/50'
100'/50'/50'
10'/100'/200' (Correct answer)
100'/100'/10'

Correct answer: 10'/100'/200'

When a Commercial Motor Vehicle (CMV) is stopped on a divided highway, federal regulations require the placement of warning devices (reflectors or triangles) at specific distances. One should be placed 10 feet behind the vehicle, another 100 feet behind, and a third 200 feet behind the vehicle, all in the center of the lane of travel. This provides ample warning to approaching traffic.

Question 10: WHAT 3 KINDS OF EMERGENCY EQUIPMENT SHOULD YOU HAVE?

Flash light, tire gauge, tire inflation foam
First aid kit, bandage gauze, pain reliever
Fire extinguisher, spare electrical fuses, warning device (Correct answer)
Exterior hazard light, cell phone, wheel chock

Correct answer: Fire extinguisher, spare electrical fuses, warning device

Federal regulations for Commercial Motor Vehicles (CMVs) mandate that drivers carry specific emergency equipment. This typically includes a properly charged and inspected fire extinguisher, spare electrical fuses (unless the vehicle has circuit breakers), and warning devices such as three reflective triangles or flares. These items are crucial for addressing common emergencies like fires, electrical issues, or breakdowns that require roadside warning.

Question 11: A DRIVER SHOULD LOOK _____ AHEAD OF THE VEHICLE WHILE DRIVING.

2-5 seconds
5-10 seconds
12-15 seconds (Correct answer)
15-25 seconds

Correct answer: 12-15 seconds

Professional drivers are trained to scan the road 12 to 15 seconds ahead to anticipate potential hazards and traffic changes. This "visual lead time" allows for sufficient time to react, make decisions, and maneuver the large vehicle safely. At highway speeds, this translates to roughly a quarter-mile, providing a critical safety margin.

Question 12: NAME SOME KEY STEERING PARTS.

Tires, rims, lug nuts
Leaf springs, bellows, eye bolt
Axle, control arm, pressure plate
Spindle, tie rod, drag link (Correct answer)

Correct answer: Spindle, tie rod, drag link

The spindle, tie rod, and drag link are all fundamental components of a vehicle's steering system. The drag link connects the steering gear to the steering arm, the tie rod connects the steering arm to the steering knuckle, and the spindle is part of the steering knuckle assembly that the wheel rotates on. These parts work together to translate the driver's steering wheel input into the turning motion of the wheels.

Question 13: YOU SHOULD USE LOW BEAMS WHENEVER YOU CAN.

TRUE (Correct answer)
FALSE

Correct answer: TRUE

It is generally true that you should use low beams whenever possible, especially at night or in conditions of reduced visibility like rain or fog. Low beams provide sufficient illumination for most driving situations without blinding oncoming drivers or drivers you are following. High beams should only be used when there is no oncoming traffic and you are not following another vehicle closely.

Question 14: WHAT IS A "HAZARD"?

Any road condition or user (driver, cyclist, pedestrian) that is a possible danger (Correct answer)
Any obstacle in the roadway
Anything that obstructs the roadway
A game of chance

Correct answer: Any road condition or user (driver, cyclist, pedestrian) that is a possible danger

A 'hazard' in driving refers to any potential danger that could lead to an accident. This includes not only physical obstacles on the road but also other road users like drivers, cyclists, or pedestrians whose actions could create a dangerous situation. Recognizing and anticipating these potential dangers is a critical part of defensive driving.

Question 15: WHY SHOULD YOU BACK TOWARD THE DRIVER'S SIDE?

State law requires backing toward the driver's side
Because it takes less time
Because you can see better (Correct answer)
So you won't have to look over your passenger

Correct answer: Because you can see better

Backing toward the driver's side provides the driver with the best possible visibility of the vehicle's path and surroundings. By looking over your left shoulder and using your left side mirror, you have a direct and unobstructed view of where your vehicle is going. This significantly reduces blind spots and helps prevent accidents while backing up.

Question 16: IF STOPPED ON A HILL, HOW CAN YOU START MOVING WITHOUT ROLLING BACK?

Place wheel chock under front wheel
Place wheel chock under rear wheel
Partly engage clutch before taking your foot off the brake (Correct answer)
Use your parking brake

Correct answer: Partly engage clutch before taking your foot off the brake

When stopped on a hill, you can prevent rolling back by partly engaging the clutch before taking your foot off the brake. This technique, often called 'finding the friction point,' allows the engine's power to hold the vehicle stationary or begin moving forward smoothly. It's a crucial skill for manual transmission drivers to ensure a safe start on inclines.

Question 17: WHAT 3 THINGS ADD UP TO TOTAL STOPPING DISTANCE?

Stopping distance/ reaction distance/ perception distance
Vehicle distance/ stopping distance/ reaction distance
Braking distance/ obstacle distance/ stopping distance
Perception distance/ reaction distance/ braking distance (Correct answer)

Correct answer: Perception distance/ reaction distance/ braking distance

Total stopping distance is the sum of three distinct phases: perception distance, reaction distance, and braking distance. Perception distance is how far your vehicle travels from when you see a hazard until your brain recognizes it. Reaction distance is how far you travel from when your brain tells your foot to move until you actually apply the brakes. Braking distance is how far your vehicle travels once the brakes are applied until it comes to a complete stop.

Question 18: RETARDERS KEEP YOU FROM SKIDDING WHEN THE ROAD IS SLIPPERY.

TRUE
FALSE (Correct answer)

Correct answer: FALSE

This statement is false. Retarders, such as engine brakes or exhaust brakes, help slow a vehicle and reduce the need for constant use of the service brakes, especially on long downgrades. However, using retarders on slippery surfaces can actually cause the drive wheels to lose traction and skid, as they apply braking force directly to those wheels. Therefore, they should be used with extreme caution or turned off in icy or wet conditions.

Question 19: WHAT ARE THE 2 SPECIAL CONDITIONS WHERE YOU SHOULD DOWNSHIFT?

Before stopping and exiting a curve
Before starting off and driving uphill
Before shutting engine off and before exiting vehicle
Before starting down a hill and before entering a curve (Correct answer)

Correct answer: Before starting down a hill and before entering a curve

You should downshift before starting down a hill to use engine braking to help control your speed and prevent your service brakes from overheating. You should also downshift before entering a curve to maintain better control and have the appropriate gear for accelerating out of the curve. These actions help maintain vehicle stability and reduce wear on the service brakes.

Alabama CDL General Knowledge Practice Test # 3

HOW FAR AHEAD SHOULD YOU LOOK WHEN DRIVING?