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NJ CDL General Knowledge study materials
NJ CDL General Knowledge study resources

NJ CDL General Knowledge practice questions

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Question 1Vehicle Inspection and Basic Control

During a pre-trip inspection of a combination vehicle, how much air pressure loss is permitted in a single minute when the engine is off, the parking brakes released, and the service brakes fully applied?

  1. No more than 1 psi
  2. No more than 2 psi
  3. No more than 3 psi Correct answer.
  4. No more than 4 psi

Explanation

For a combination vehicle, the air brake leak-down test with the engine off and the service brakes fully applied allows a loss of no more than 3 psi in one minute. A single vehicle is held to 2 psi, so the combination figure is the looser threshold. More than 3 psi indicates a leak that must be fixed before driving.

Question 2Vehicle Inspection and Basic Control

While checking slack adjusters during a pre-trip inspection, you find one with about two inches of free play at the push rod. What does this indicate?

  1. The push rod length should be shortened
  2. The brake is correctly set for normal operation
  3. The slack adjuster only needs fresh grease
  4. The brake is out of adjustment and the vehicle should be placed out of service Correct answer.

Explanation

Excessive push rod travel means the foundation brake is out of adjustment and may not apply full braking force. Roughly two inches of free play is well beyond the normal range for most automatic slack adjusters. The vehicle should be tagged out of service until the brake is repaired.

Question 3Vehicle Inspection and Basic Control

You are inspecting a tractor-trailer and notice the fifth wheel locking jaws are not fully closed around the kingpin. What is the correct action?

  1. Drive slowly and recheck after a few miles
  2. Do not move the vehicle until the coupling is corrected and verified Correct answer.
  3. Release the trailer brakes and pull forward gently
  4. Tap the kingpin with a hammer and continue

Explanation

The locking jaws must completely close around the kingpin or the trailer can separate from the tractor. A positive pull test with the trailer brakes set confirms a secure coupling. An improperly locked fifth wheel makes the combination unsafe to move at any speed.

Question 4Vehicle Inspection and Basic Control

When performing the tug test on a coupled trailer, what should you do?

  1. Release all brakes and accelerate to highway speed
  2. Apply only the tractor brakes and reverse
  3. Set the trailer parking brakes, shift into a low gear, and gently pull against them Correct answer.
  4. Chock the wheels and lower the landing gear

Explanation

The tug test checks that the fifth wheel has locked onto the kingpin. With the trailer brakes set, a gentle pull in low gear should not move the trailer relative to the tractor. Any movement or separation signals an incomplete coupling.

Question 5Vehicle Inspection and Basic Control

During a pre-trip inspection you find a small puddle of coolant under the engine and the reservoir below the minimum line. What is the appropriate response?

  1. Tighten the radiator cap and continue
  2. Add water and complete the trip as planned
  3. Identify and repair the leak before operating the vehicle Correct answer.
  4. Ignore it because coolant expands when hot

Explanation

A coolant leak combined with a low reservoir indicates a defect that can lead to overheating and engine damage. The source must be found and corrected before the vehicle is operated. Topping off fluid without fixing the leak only postpones the failure.

Question 6Vehicle Inspection and Basic Control

What is the proper way to check tire tread depth on a commercial vehicle during a pre-trip inspection?

  1. Measure the tread grooves with a gauge at several points around each tire Correct answer.
  2. Squeeze the tread with your fingers
  3. Look only at the outer edge of the tire
  4. Kick the sidewall and listen for a solid sound

Explanation

Tread depth must be measured with a gauge in the major grooves at multiple locations around the tire. Visual or physical estimates are unreliable and can miss wear in one area. Measuring also helps detect uneven wear that points to alignment or inflation problems.

Question 7Vehicle Inspection and Basic Control

Before backing a tractor-trailer, which step best reduces the risk of a collision?

  1. Rely only on the left mirror
  2. Get out and check the area behind the trailer, then use a helper or mirrors while backing Correct answer.
  3. Back toward the driver side without checking
  4. Sound the horn continuously and back quickly

Explanation

Large blind spots behind a trailer make a walk-around check essential before backing. Using a helper or careful mirror checks keeps the path clear as you move. Backing quickly or relying on one mirror leaves unseen hazards.

Question 8Vehicle Inspection and Basic Control

You must make a right turn in a tractor-trailer at a tight intersection. What technique helps prevent the trailer from striking the curb?

  1. Turn sharply at the last moment
  2. Stay in the right lane and turn from the far right edge
  3. Accelerate through the turn to shorten it
  4. Swing wide to the left before turning while keeping the rear wheels clear of the curb Correct answer.

Explanation

Off-tracking causes the trailer's rear wheels to cut inside the tractor's path on a turn. Swinging wide before the turn allows the trailer to clear the curb. Turning too sharply or too fast increases the chance of hitting the curb or a nearby object.

Question 9Vehicle Inspection and Basic Control

When driving a loaded combination vehicle, what is the safe following distance rule under normal conditions?

  1. Half the posted speed limit in feet
  2. One second total regardless of length
  3. Two car lengths behind the vehicle ahead
  4. At least one second for each ten feet of vehicle length plus one second Correct answer.

Explanation

A common rule is one second per ten feet of vehicle length plus one extra second for speeds above 40 mph. A 60-foot combination therefore needs about seven seconds. Longer and heavier vehicles need more stopping distance than passenger cars.

Question 10Vehicle Inspection and Basic Control

What is the purpose of the stab braking method when stopping a vehicle without ABS?

  1. To pump the brakes lightly and continuously
  2. To hold the brake pedal down until the vehicle stops
  3. To apply the brakes fully, release when wheels lock, and reapply to regain steering control Correct answer.
  4. To downshift through every gear while braking

Explanation

Stab braking means pressing the brake pedal firmly until the wheels lock, releasing, and reapplying as needed. This restores steering control when wheels skid. Holding the brakes locked removes steering and lengthens the skid.

Question 11Vehicle Inspection and Basic Control

You are driving a tanker with a partial load of liquid and must stop quickly. What should you expect?

  1. The load will stay fixed and stopping distance is unchanged
  2. The liquid will surge forward and can push the vehicle, so allow extra stopping distance Correct answer.
  3. The vehicle will stop faster because the load is lighter
  4. The brakes will apply more evenly than with a full load

Explanation

Liquid in a partially filled tank shifts forward during braking and adds force that can lengthen stopping distance. The surge can also affect steering and stability. Drivers should reduce speed and leave more room when hauling partial liquid loads.

Question 12Vehicle Inspection and Basic Control

When starting from a stop on an upgrade with a heavy manual-transmission truck, what technique helps prevent rolling backward?

  1. Hold the clutch pedal halfway down and coast
  2. Engage the clutch gradually while releasing the parking brake as the clutch begins to grab Correct answer.
  3. Release the parking brake first, then accelerate
  4. Shift into a higher gear to reduce wheel spin

Explanation

On an upgrade, the clutch should begin to engage before the parking brake is fully released. This holds the vehicle while power reaches the wheels. Releasing the brake first allows the truck to roll back before the clutch engages.

Question 13Vehicle Inspection and Basic Control

What does the term off-tracking describe when operating a long combination vehicle?

  1. The steering axle wandering at highway speed
  2. The trailer wheels drifting outward on a curve
  3. The rear wheels of the trailer follow a path inside the path of the front wheels Correct answer.
  4. The brakes pulling to one side

Explanation

Off-tracking is the tendency of the rear wheels to cut a shorter path than the front wheels in a turn. The longer the vehicle, the greater the difference. Drivers must allow for this when turning and changing lanes.

Question 14Vehicle Inspection and Basic Control

During a pre-trip inspection, you notice that the left turn signal on the trailer does not flash. What should you do?

  1. Proceed if the tractor signal works
  2. Dispatch the vehicle and report it at the end of the day
  3. Repair the faulty light before the vehicle is dispatched Correct answer.
  4. Use hand signals instead

Explanation

All required lights must work before the vehicle is operated. A non-functioning turn signal is a safety defect that must be corrected. Hand signals and verbal reports do not substitute for working equipment.

Question 15Vehicle Inspection and Basic Control

You are checking the engine compartment during a pre-trip inspection. Which item should be checked for proper tension and condition?

  1. The exhaust manifold bolts
  2. The drive belts Correct answer.
  3. The fuel gauge
  4. The steering column

Explanation

Drive belts should be checked for cracks, glazing, and correct tension during the engine compartment inspection. A loose or worn belt can fail and disable components such as the alternator or cooling fan. The other items are not belt-driven components checked for tension.

Question 16Vehicle Inspection and Basic Control

When should the parking brake be set during the uncoupling process?

  1. After lowering the landing gear
  2. After pulling the tractor forward
  3. After disconnecting the air lines
  4. Before releasing the fifth wheel locking jaws Correct answer.

Explanation

The trailer parking brake must be set before the fifth wheel is released so the trailer cannot roll. Landing gear should be lowered and the trailer supported before the tractor is pulled away. Releasing the jaws first risks an uncontrolled trailer.

Question 17Vehicle Inspection and Basic Control

You are descending a long steep grade with a heavy load. Which approach is safest?

  1. Coast in neutral and use the service brakes
  2. Rely on the trailer brakes alone
  3. Use the highest gear and brake hard when needed
  4. Select a lower gear before the descent and use engine braking to control speed Correct answer.

Explanation

A lower gear before the grade lets engine braking hold speed and prevents brake fade. Coasting in neutral removes engine braking and lets speed build. Relying on service brakes alone on a long grade can overheat them.

Question 18Vehicle Inspection and Basic Control

What is the first thing to check when you suspect the air brake system is not building pressure properly?

  1. Whether the compressor is building pressure and the gauge rises to the normal range Correct answer.
  2. Whether the tires are properly inflated
  3. Whether the horn sounds
  4. Whether the trailer lights are working

Explanation

Low or slow-building air pressure points to a compressor or leak problem. Watching the gauge during build-up confirms whether the system reaches normal operating pressure. The other checks are unrelated to air pressure build.

Question 19Vehicle Inspection and Basic Control

When checking the service brake during a pre-trip inspection, what should you observe?

  1. That the pedal feels soft and travels fully
  2. That the brake lights stay on
  3. That the vehicle slows and stops without pulling to one side Correct answer.
  4. That the wheels lock immediately

Explanation

A service brake check confirms the vehicle slows and stops smoothly without pulling. Pulling to one side suggests an uneven or faulty brake. A soft pedal or immediate wheel lock indicates a problem rather than correct operation.

Question 20Vehicle Inspection and Basic Control

You are driving a tractor-trailer and the trailer begins to swing side to side in a skid. What is the correct response?

  1. Apply the brakes harder and hold the wheel straight
  2. Accelerate to pull the trailer straight
  3. Turn the wheel sharply opposite the swing
  4. Release the brakes to regain traction and steer in the direction you want to go Correct answer.

Explanation

Releasing the brakes allows the wheels to roll and regain traction. Steering in the intended direction helps bring the vehicle back under control. Hard braking or sharp counter-steering can worsen the skid.

Question 21Vehicle Inspection and Basic Control

What is the effect of a load that is placed too far forward on the trailer?

  1. It has no effect on axle weights
  2. It adds weight to the steering axle and can reduce steering control Correct answer.
  3. It shifts weight to the trailer brakes only
  4. It lightens the steering axle and improves traction

Explanation

A load placed too far forward transfers weight onto the drive and steering axles. Overloading the steering axle can make steering feel heavy and reduce control. Proper load placement keeps weight within each axle's rating.

Question 22Vehicle Inspection and Basic Control

During a pre-trip inspection you find that the emergency (spring) brake does not apply when air pressure drops. What is the correct action?

  1. Reduce speed and complete the route
  2. Set the trailer brakes and continue
  3. Place the vehicle out of service until the brake system is repaired Correct answer.
  4. Pump the brakes to restore pressure and drive

Explanation

Spring brakes must apply automatically when air pressure falls below a safe level. A failure of this function is a serious defect that could leave the vehicle without parking or emergency braking. The vehicle must be repaired before it is operated.

Question 23Vehicle Inspection and Basic Control

You are backing a trailer that is angled to the left, and the trailer begins to turn more sharply than intended. What should you do?

  1. Turn the wheel further in the same direction
  2. Straighten the steering wheel to stop the trailer from turning further Correct answer.
  3. Accelerate to correct the angle
  4. Apply the trailer brakes only

Explanation

When a trailer turns more sharply than desired while backing, straightening the wheel stops further rotation of the trailer. Continuing the same steering input increases the angle. Correcting early prevents a jackknife.

Question 24Vehicle Inspection and Basic Control

What is the correct sequence for a pre-trip inspection of a combination vehicle?

  1. Check lights last after driving a short distance
  2. Check the brakes first, then start the engine
  3. Start with the engine compartment and coupling, then check lights, brakes, and the walk-around Correct answer.
  4. Begin with the trailer lights and skip the engine

Explanation

A systematic inspection starts with the engine compartment and coupling, then moves to lights, brakes, and the walk-around. This order ensures nothing is missed before the vehicle is operated. Skipping steps or checking after driving defeats the purpose.

Question 25Shifting, Backing, and Turning

When you are shifting a manual transmission in a heavy commercial vehicle, at what point should you move the gearshift lever into the next gear?

  1. After the engine has returned to idle rpm
  2. While the clutch pedal is pressed fully to the floor Correct answer.
  3. Only after the tachometer drops below 800 rpm
  4. Before pressing the clutch pedal at all

Explanation

The clutch must be fully disengaged before the lever moves, otherwise the transmission gears drag and clash. Pushing the pedal to the floor separates the engine from the driveline so the shift can be completed without grinding.

Question 26Shifting, Backing, and Turning

You are driving a tractor-trailer with a nonsynchronized (constant mesh) transmission. What technique helps match engine speed to road speed during an upshift?

  1. Double clutching, releasing the clutch in neutral Correct answer.
  2. Skipping every other gear to save time
  3. Power shifting without releasing the accelerator
  4. Holding the clutch pedal halfway down while shifting

Explanation

In a nonsynchronized transmission the gears must be matched by the driver, and double clutching lets the engine and input shaft speed align before the gear is engaged. Releasing the clutch in neutral and blipping the throttle synchronizes the shafts so the gear slides in without clashing.

Question 27Shifting, Backing, and Turning

Before backing a large combination vehicle, what is the correct first step?

  1. Get out and walk around the vehicle to check for obstacles and people Correct answer.
  2. Ask a passenger to watch from the cab's right seat
  3. Rely on the convex mirrors alone to clear the path
  4. Sound the horn twice and back immediately

Explanation

The area behind a large vehicle is a blind spot, so the driver must physically inspect it before reversing. Walking around confirms clearance, identifies hazards, and lets you plan the backing path before any wheel moves.

Question 28Shifting, Backing, and Turning

When backing a tractor-trailer, in which direction should you turn the steering wheel to make the rear of the trailer move to the driver's left?

  1. Turn the wheel to the left
  2. Turn the wheel left, then immediately right
  3. Hold the wheel straight and let the trailer drift
  4. Turn the wheel to the right Correct answer.

Explanation

When backing, the trailer pivots opposite the steering input, so turning the wheel right pushes the trailer's rear to the left. The driver must steer opposite the desired trailer direction and then follow with corrective steering to keep the unit straight.

Question 29Shifting, Backing, and Turning

You are backing a tractor-trailer and the trailer begins to jackknife toward the right. What is the safest corrective action?

  1. Continue backing slowly and let the angle correct itself
  2. Accelerate to pull the trailer straight
  3. Crank the wheel further right to catch the swing
  4. Stop, pull forward to straighten the unit, then resume backing Correct answer.

Explanation

Once the angle grows beyond a controllable point, continuing to back tightens the jackknife and can damage the equipment or strike objects. Stopping and pulling forward resets the geometry so you can realign the tractor and trailer before backing again.

Question 30Shifting, Backing, and Turning

When making a right turn in a large commercial vehicle, why should you turn wide as needed while completing the turn?

  1. To shorten the distance traveled through the intersection
  2. To signal other drivers that you are turning
  3. To increase speed through the corner
  4. To keep the rear wheels from running over the curb or a pedestrian Correct answer.

Explanation

Large vehicles have off-tracking, meaning the rear wheels follow a path inside the front wheels. If extra turning room is needed, obtain it while completing the turn to keep the rear wheels clear of curbs and pedestrians. Do not swing left before starting the right turn, because other drivers may try to pass on the right.

Question 31Shifting, Backing, and Turning

A commercial vehicle is approaching an intersection to turn right, and a bicyclist is riding in the bike lane on the right. What should the driver do?

  1. Turn right ahead of the bicyclist to stay in front
  2. Sound the horn and proceed with the turn
  3. Move into the bike lane and accelerate past the bicyclist
  4. Wait behind the bicyclist and complete the turn only when the lane is clear Correct answer.

Explanation

A right-turning large vehicle can trap a cyclist between the vehicle and the curb, a leading cause of serious collisions. The driver should hold back, let the cyclist clear the intersection, and then complete the turn.

Question 32Shifting, Backing, and Turning

When must you use a turn signal before changing lanes or turning in a commercial vehicle?

  1. Whenever you feel it is necessary for safety
  2. At least 100 feet before the maneuver in most states Correct answer.
  3. Only after you have begun the maneuver
  4. Only when other vehicles are visibly nearby

Explanation

Commercial driving rules generally require signaling well in advance of a turn or lane change so surrounding traffic can react. The common standard is at least 100 feet before the maneuver, and some states require more at higher speeds.

Question 33Shifting, Backing, and Turning

You are driving a long combination vehicle and need to turn around. Which maneuver is generally safest and legal?

  1. A three-point turn on a narrow residential street
  2. Backing into a driveway to reverse direction Correct answer.
  3. A U-turn across a divided highway median
  4. A U-turn at an intersection with a green light

Explanation

Large vehicles have wide turning radii and blind spots, so U-turns and multi-point turns in traffic are risky and often illegal. Backing into a driveway or side street lets the driver reverse out of traffic flow and re-enter in the opposite direction with better control.

Question 34Shifting, Backing, and Turning

What is the recommended way to use mirrors while backing a commercial vehicle?

  1. Watch only the driver's side mirror throughout
  2. Alternate between both flat mirrors and check the rear frequently Correct answer.
  3. Rely on the convex mirror for precise distance judgment
  4. Keep your eyes on the backup camera screen the entire time

Explanation

Backing requires continuous scanning of both sides because hazards can appear on either side of the vehicle. Alternating between the flat mirrors gives the most accurate view, while convex mirrors and cameras supplement but distort distance.

Question 35Shifting, Backing, and Turning

A driver must back a tractor-trailer around a corner into a loading dock on the left. What is the best approach?

  1. Back straight in from the center of the roadway
  2. Back from the right side of the roadway so the trailer swings left
  3. Approach from the far left lane and cut sharply across traffic
  4. Position the tractor so the trailer sets up on the driver's side of the dock Correct answer.

Explanation

Setting up so the trailer is on the driver's side gives the best visibility and lets the driver sight down the trailer's side while backing. This reduces blind-side backing, which is far more dangerous because the driver cannot see the trailer's path.

Question 36Shifting, Backing, and Turning

When shifting a manual transmission while climbing a steep grade, what should you do to maintain power?

  1. Hold the current gear until the engine stalls
  2. Downshift before the engine lugs or loses power Correct answer.
  3. Upshift early to keep engine rpm low
  4. Coast in neutral to gain speed

Explanation

On a grade, engine load rises and road speed falls, so the driver must downshift before the engine lugs to stay in the power band. Waiting until the engine bogs down risks stalling and losing momentum on the hill.

Question 37Shifting, Backing, and Turning

What does progressive shifting mean in the context of commercial vehicle operation?

  1. Shifting only when the tachometer reaches the redline
  2. Upshifting at progressively higher rpm as road speed increases Correct answer.
  3. Skipping gears to reach top gear faster
  4. Shifting through every gear at the same engine rpm

Explanation

Progressive shifting means using lower rpm for early upshifts and higher rpm for later ones, keeping the engine in its most efficient range. This practice saves fuel and reduces wear while maintaining adequate power for the load.

Question 38Shifting, Backing, and Turning

Before making a lane change in a commercial vehicle, what is the proper sequence of actions?

  1. Check mirrors, signal, accelerate, then move
  2. Signal and move simultaneously while watching ahead
  3. Honk, check the mirror, and change lanes
  4. Signal, check mirrors, check blind spots, then move Correct answer.

Explanation

The correct sequence signals intent, verifies the space through mirrors, and confirms the blind spot before the vehicle moves. Checking the blind spot is essential because mirrors do not cover the area beside and behind the trailer.

Question 39Shifting, Backing, and Turning

While backing a straight truck, you notice a pedestrian walking behind the vehicle. What should you do?

  1. Sound the horn and keep backing
  2. Continue backing slowly and expect the pedestrian to move
  3. Stop immediately and wait until the pedestrian is clear Correct answer.
  4. Speed up to clear the area quickly

Explanation

A pedestrian behind a backing vehicle has the right of way, and the driver's view may be obstructed. Stopping immediately and waiting until the person is clear prevents a collision and keeps the driver in control.

Question 40Shifting, Backing, and Turning

Why should a driver avoid coasting with the clutch pedal depressed or the transmission in neutral while the vehicle is moving downhill?

  1. It increases fuel consumption significantly
  2. It removes engine braking and reduces control on the grade Correct answer.
  3. It causes the tachometer to read incorrectly
  4. It improves steering response at high speed

Explanation

With the clutch disengaged or the transmission in neutral, the engine no longer slows the vehicle through engine braking. On a downgrade this loss of retardation can lead to overheating brakes and reduced control, and coasting is prohibited in many jurisdictions.

Question 41Seeing and Communicating

Under New Jersey law, when must a driver turn on the vehicle's headlights?

  1. Only when other drivers flash their high beams
  2. Only on unlit rural roads at night
  3. Whenever visibility is 500 feet or less, or during rain, snow, fog, or mist Correct answer.
  4. Only between sunset and sunrise

Explanation

New Jersey requires headlights whenever there is not sufficient light to see persons and vehicles on the highway at a distance of 500 feet, and also whenever rain, snow, fog, mist, or other moisture is falling and wipers are in use. Turning them on early helps other drivers see you, not just you see them.

Question 42Seeing and Communicating

What is the proper way to use high-beam headlights when a vehicle approaches you from the opposite direction at night?

  1. Switch to parking lights only
  2. Flash high beams repeatedly to signal the other driver
  3. Keep high beams on until the vehicle passes to maintain your view
  4. Dim to low beams within 500 feet of the oncoming vehicle Correct answer.

Explanation

High beams must be dimmed when an oncoming vehicle comes within 500 feet, and when following another vehicle within 200 feet. Glare can temporarily blind an oncoming driver, so dimming protects both of you.

Question 43Seeing and Communicating

Why should a CDL driver check the mirrors more frequently when driving in heavy traffic?

  1. Mirrors show the blind spots directly behind the trailer
  2. Mirror checks are required only when backing
  3. Checking mirrors reduces fuel consumption
  4. Frequent mirror checks reveal vehicles moving into your no-zone areas and changing lane positions Correct answer.

Explanation

Blind spots on a large vehicle are extensive, and traffic can move into those areas quickly. Regular mirror scans give you time to react before a lane change or stop, and they help you track vehicles that disappear from view.

Question 44Seeing and Communicating

A commercial driver is approaching a work zone with a flagger holding a paddle that reads SLOW. What is the correct response?

  1. Stop completely and wait for the flagger to wave you through
  2. Reduce speed and proceed with caution as directed Correct answer.
  3. Sound the horn to warn the workers and continue
  4. Maintain highway speed and follow the vehicle ahead closely

Explanation

A SLOW paddle directs drivers to reduce speed and continue cautiously, staying alert for workers and equipment. Work-zone speeds are enforced, and fines for violations are commonly doubled in these areas.

Question 45Seeing and Communicating

When driving at night, where should you look to reduce glare from oncoming headlights?

  1. Toward the right edge of your lane or the fog line Correct answer.
  2. At the center line of the road
  3. At your dashboard instruments
  4. Directly at the oncoming headlights

Explanation

Looking toward the right edge of your lane keeps your eyes adjusted while oncoming headlights pass, and it preserves your lane position. Staring at the lights increases glare and slows your recovery of night vision.

Question 46Seeing and Communicating

What does a flashing yellow arrow at an intersection mean for a commercial driver?

  1. The signal is broken and you should treat it as a stop sign
  2. You may turn in the direction of the arrow after yielding to oncoming traffic and pedestrians Correct answer.
  3. Proceed with a protected turn only
  4. Stop and wait for a green arrow

Explanation

A flashing yellow arrow permits the turn but does not give right-of-way, so you must yield to oncoming vehicles and pedestrians. It is different from a solid green arrow, which provides a protected turn.

Question 47Seeing and Communicating

You are driving a tractor-trailer and want to change lanes on a multi-lane highway. Which sequence best supports a safe lane change?

  1. Rely on the vehicle's lane-departure warning and change lanes
  2. Check mirrors once, then accelerate and move over quickly
  3. Signal and change lanes immediately so other drivers know your intent
  4. Signal, check mirrors, check the blind spot over your shoulder, then move smoothly Correct answer.

Explanation

Mirrors alone do not cover the blind spots beside a long combination vehicle, so a shoulder check is needed before moving. Signaling early and moving smoothly gives surrounding traffic time to react.

Question 48Seeing and Communicating

In fog, why should a driver avoid using high-beam headlights?

  1. High beams are illegal in all weather conditions
  2. High beams reflect off the fog and create glare that reduces visibility Correct answer.
  3. High beams drain the battery faster
  4. High beams make the vehicle appear larger to others

Explanation

High beams project light upward and forward, and in fog that light bounces back into the driver's eyes. Low beams aim lower and reduce the glare, and fog lights can further improve visibility near the road surface.

Question 49Seeing and Communicating

A school bus ahead of you has stopped with its red lights flashing on a two-lane road with no median. What must you do?

  1. Honk to warn the bus driver and proceed
  2. Stop only if children are visible
  3. Stop and remain stopped until the red lights stop flashing Correct answer.
  4. Slow down and pass carefully on the left

Explanation

On an undivided road, traffic in both directions must stop for a school bus displaying flashing red lights and an extended stop arm. You may proceed only after the lights stop flashing and the arm is retracted.

Question 50Seeing and Communicating

Your tractor-trailer begins to skid on a wet roadway. What is the recommended steering response?

  1. Release the wheel and let the vehicle correct itself
  2. Turn the steering wheel sharply against the direction of the skid
  3. Hold the wheel straight and brake hard
  4. Steer in the direction you want the front of the vehicle to go Correct answer.

Explanation

Steering where you want the front of the vehicle to go helps the tires regain traction and aligns the vehicle with the road. Sharp counter-steering or hard braking can worsen the skid, especially in a heavy combination vehicle.