General Knowledge · Practice test 7

Question 1Not answered

Why is braking while turning more likely to cause a skid than braking while going straight?

1. Braking and turning never interact in terms of available traction
2. Braking while turning only matters above highway speed, not at slower speeds, though that's not how straight actually works
3. Turning already uses up some of the tire's available traction, leaving less margin for braking forces
4. It only matters for vehicles without power steering

Question 2Not answered

How long should you wait to drive after drinking alcohol, as a matter of safe practice?

1. Wait exactly one hour per drink
2. Allow enough time for all the alcohol to leave your body completely, not just until you feel sober
3. Drink coffee and drive immediately afterward
4. Drive once you feel fine, since how you feel is a more reliable measure than the clock, though the reality of practice says otherwise

Question 3Not answered

Why should you slow down before reaching a curve rather than while already in it?

1. Slowing beforehand mainly matters in wet weather, not on a dry road
2. Braking while turning shifts weight in a way that can reduce tire grip and increase rollover risk
3. Braking in a curve always improves traction compared to braking beforehand, a shortcut that doesn't actually apply to already
4. It makes no difference when you brake, as long as you slow down eventually

Question 4Not answered

How long must a driver generally wait after consuming alcohol before operating a commercial motor vehicle, under federal rules?

1. There is no required waiting period as long as the driver feels sober
2. Only until the next calendar day begins, regardless of the time consumed
3. Thirty minutes
4. At least four hours

Question 5Not answered

What should you do if a tire blows out while driving at highway speed?

1. Brake hard immediately to slow down before the vehicle starts to pull, which some drivers pick up wrong about speed
2. Accelerate to maintain stability
3. Hold the steering wheel firmly, ease off the accelerator, and brake gently once the vehicle is under control
4. Brake hard immediately, regardless of steering control

Question 6Not answered

Why is it especially important to check tire chains, batteries, and antifreeze before winter trips?

1. Cold weather mainly affects tire pressure, not batteries or antifreeze performance, something that trips up drivers unfamiliar with trips
2. Cold weather puts extra strain on these systems, and a failure in freezing conditions is more dangerous to deal with
3. These checks are only relevant in summer heat, not winter cold
4. This check replaces the need for a normal pre-trip inspection

Question 7Not answered

Why does entering an intersection require extra space awareness compared to open road driving?

1. Intersections are covered by traffic signals, so space management matters less there than on the open road
2. Traffic signals remove the need to judge space yourself
3. Vehicles from multiple directions could cross your path with little warning, so you need room to react
4. Space management only applies to highway driving

Question 8Not answered

What should you do about your own vehicle's hazard lights immediately after being involved in a roadway crash?

1. Only turn them on if the crash happened at night
2. Wait for police to arrive before turning them on
3. Leave them off to save the battery until help arrives
4. Turn them on right away to alert approaching traffic

Question 9Not answered

What is the basic purpose of an emergency response guidebook that responders (and sometimes drivers) keep on hand?

1. It provides quick guidance on handling specific hazardous materials safely in an emergency
2. It is only used to calculate fuel surcharges
3. It replaces the need for any hazmat-specific training
4. It applies only to shipments crossing an international border, something that rarely comes up around hand

Question 10Not answered

Why can some over-the-counter medications be just as dangerous to drive on as alcohol?

1. Medication only affects driving if taken in combination with caffeine
2. Over-the-counter medications only affect driving ability if taken in double the normal dose
3. Certain medications cause drowsiness or slowed reaction time similar to the effects of alcohol
4. Only prescription medications carry any risk, never over-the-counter ones

Question 11Not answered

Why should you check your mirrors regularly, not just when you plan to change lanes?

1. To save time compared to checking gauges
2. To know the situation around your vehicle at all times, including problems developing before you need to react
3. Mirrors matter more than watching the road ahead, since rear-end hazards are more common than ones ahead of you
4. To check your appearance while driving

Question 12Not answered

Why should you check clearance for a tall load before departing, not just before reaching a low bridge?

1. Overhead hazards other than bridges don't affect tall loads
2. There may be other overhead hazards along the route, like wires or awnings, not only official bridge clearances
3. Clearance only ever needs to be checked once, right before the trip begins, something that rarely comes up around bridge
4. Checking clearance only matters on routes with more than one low bridge

Question 13Not answered

Before starting a trip, you find that one of the trailer's brake lights does not come on. What should you do?

1. Tap the brake pedal harder to compensate for the missing light
2. Continue the trip and mention it at your next scheduled service appointment, since one light rarely matters
3. Drive only during the day so the light isn't needed
4. Have the light fixed or replaced before driving, since other drivers rely on it to know you're slowing down

Question 14Not answered

During the air brake check, what should you do to test that the trailer's brakes actually apply when the trailer supply valve is closed?

1. Rely on the dashboard warning light alone with no physical check
2. There is no way to test this before driving
3. Close the valve and confirm the trailer brakes set, often by trying to pull against them gently
4. Only check that the trailer's air lines are still connected properly, though that's not how closed actually works

Question 15Not answered

Why should a driver stay aware of how prescription medications might affect their driving over time?

1. This only matters when a dose is increased, not for a prescription already stable, an idea that doesn't match how time works
2. Prescription medications never affect alertness or reaction time
3. Once a prescription is approved, its effects never change over time
4. Side effects can change as dosage changes or as a new medication is combined with an existing one

Question 16Not answered

What can happen if cargo is not properly secured and shifts during a hard turn?

1. Shifting cargo only matters for liquid loads, not solid freight
2. It only becomes a problem after the truck has already stopped
3. It has no effect on handling as long as the cargo stays inside the trailer
4. It can throw off the vehicle's balance and contribute to a rollover

Question 17Not answered

You notice a large crack across your windshield directly in your line of sight during inspection. What should you do?

1. Tape over the crack so it doesn't spread further
2. Continue as planned, since a crack usually stays the same size unless the glass is hit again
3. Have it repaired or replaced before driving, since it blocks a clear view of the road
4. Drive only during the day when visibility is naturally better

Question 18Not answered

While backing into a space, you realize the angle is wrong and you're about to hit a curb. What should you do?

1. Turn the wheel as far as it goes and continue backing at the same pace
2. Pull forward, reposition, and start the backing maneuver again
3. Keep backing and try to correct the angle at the last second
4. Speed up slightly so momentum straightens the trailer

Question 19Not answered

Why is smooth clutch and accelerator coordination especially important when the vehicle is fully loaded?

1. A loaded vehicle needs more time and torque to get moving, so jerky control can stall the engine or roll the vehicle back
2. It only matters for looks, since a jerky start doesn't affect the cargo
3. Coordination matters less when loaded, since the added weight steadies the whole vehicle, something few drivers think about with loaded
4. Loaded vehicles have a different pedal layout that requires special coordination

Question 20Not answered

Why should you reduce speed when driving in fog, even if you cannot see any other vehicles nearby?

1. Reducing speed in fog is only a legal requirement, not an actual safety benefit, though that is not correct
2. Fog has no real effect on stopping distance
3. Fog only affects visibility for pedestrians, not drivers
4. Fog reduces how far ahead you can see, which shortens the distance you have to react to a hazard

Question 21Not answered

After the scene of an accident has been made safe, what should you do regarding your employer or dispatcher?

1. Report the accident to them as required, once the immediate safety concerns are handled
2. There is no need to report an accident unless a vehicle needed to be towed, which surprises a lot of drivers new to dispatcher
3. Wait until you return from the entire trip before mentioning it
4. Reporting is optional and left entirely to the driver's judgment

Question 22Not answered

Why do motorcycles require extra attention when scanning traffic for hazards?

1. Their smaller size makes them easier to misjudge in distance and speed, and easier to lose in a blind spot
2. Motorcycles are always easier to see than cars at any distance
3. Motorcycles are required to travel slower than other traffic
4. Motorcycles are required to stay in the far right lane near commercial vehicles, which some drivers pick up wrong about hazards

Question 23Not answered

What does it mean to identify a hazard 'early' rather than just quickly?

1. Reacting to a hazard the instant it becomes an emergency
2. Only relevant to hazards you can see from a great distance, such as construction signs
3. Waiting until another driver reacts first, then following their lead
4. Recognizing a developing risk well before it forces an emergency reaction

Question 24Not answered

When should you use your horn to communicate with other drivers?

1. Continuously while driving in heavy traffic
2. As a greeting to other commercial drivers
3. Whenever changing lanes, instead of using your turn signal to warn nearby traffic
4. Only when needed to avoid a hazard, since overuse startles others without helping

Question 25Not answered

What should you do to prepare your vision before starting a night drive?

1. Avoid looking at bright lights right before driving so your eyes are already adjusted to darkness
2. Wear sunglasses to reduce glare from your own headlights
3. Vision preparation makes no difference for night driving
4. Keep the cab as brightly lit as possible right up until you start driving, a habit that's hard to unlearn around drive

Question 26Not answered

As part of the whole vehicle air brake check, why do you also check that the trailer's brakes hold when the tractor protection valve is tested?

1. It measures the trailer's total cargo weight indirectly
2. It confirms the trailer's emergency brakes will apply correctly if the air supply to the trailer is ever lost
3. This test is only relevant for trailers built before the mid-1990s, an assumption that doesn't hold up with tested
4. It only checks the trailer's turn signals, not its brakes

Question 27Not answered

You notice a ball roll into the street from between parked cars in a residential area. What should this make you anticipate?

1. A child may run into the street after the ball, so you should be ready to stop
2. That parked cars in the area will start pulling out at the same time
3. Nothing in particular, since the ball is not itself a hazard to the vehicle
4. That the street is about to be closed for a game

Question 28Not answered

Why should you reduce speed before entering a curve rather than while already in it?

1. Braking mid-curve works just as well, since the tires grip the same in a turn, something that rarely comes up around already
2. Speed has no real effect on how a vehicle handles a curve
3. Braking while turning shifts weight in a way that can reduce tire grip and increase rollover or skid risk
4. It only matters for empty vehicles, not loaded ones

Question 29Not answered

Why is checking that the horn works part of a pre-trip inspection?

1. It's checked so passengers can be greeted on boarding
2. It matters mainly for city driving, not for highway trips where horns are rarely used, which surprises a lot of drivers new to inspection
3. The horn is the only way to warn another driver of an immediate hazard when there's no time for anything else
4. A working horn is required only for vehicles under 10,000 pounds

Question 30Not answered

What does it mean to 'cover the brake' when you spot a potential hazard ahead?

1. Press the brake pedal fully to the floor immediately
2. Apply the parking brake as a precaution while the vehicle is still moving, though that is not correct
3. Physically cover the brake pedal with a protective mat
4. Move your foot from the accelerator to hover over the brake pedal without pressing it yet