Speed and Stopping Distance

Stopping distance is the sum of the distance you travel while you react and the distance the brakes need. It grows much faster than speed, which is why following distance and speed limits matter.

70 practice questions with answers. These rules are the same in every state.

Speed and Stopping Distance quiz

Answer at your own pace. After each question you see the correct answer and why, and at the end a review of what you missed.

Quick quiz: 10 random questions on speed and stopping distance; pass with 8 correct.

Speed and Stopping Distance questions with answers

The road is icy and visibility is poor, but you are driving at the posted speed limit. Is this acceptable?
1. No, because you may never drive faster than is safe for the conditions
2. Yes, as long as you keep both hands on the wheel and stay alert
3. Yes, unless a temporary sign has been posted to lower the limit for the weather
4. Yes, because the posted limit is always the lawful speed on that road
Show answer

Answer A: No, because you may never drive faster than is safe for the conditions

Under the basic speed rule a driver must travel at a speed that is reasonable for the actual conditions, so a legal posted speed can still be an unlawful and unsafe speed.

Source: highways.dot.gov
What does a posted speed limit sign represent?
1. A recommended speed that carries no legal force
2. The maximum speed permitted under ideal conditions
3. The average speed of traffic on that road
4. The speed all traffic is required to maintain
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Answer B: The maximum speed permitted under ideal conditions

A speed limit is an upper limit that assumes good weather, good visibility and light traffic, so the safe speed is often lower than the posted figure.
A yellow curve warning sign carries a yellow plaque showing a speed. What does that number mean?
1. A regulatory speed limit that applies to the whole road ahead of the sign
2. The minimum speed required to hold the vehicle through the curve
3. The speed at which the curve was surveyed and has no meaning for drivers
4. The recommended maximum safe speed for the curve under ideal conditions
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Answer D: The recommended maximum safe speed for the curve under ideal conditions

An advisory speed plaque on a yellow warning sign gives the recommended maximum speed for the hazard ahead when conditions are good.
What makes up the total distance needed to bring a vehicle to a stop?
1. The distance covered while you perceive the hazard, the distance covered while you react, and the braking distance
2. The length of your own vehicle plus one extra car length for every ten miles per hour
3. Only the distance covered once the brakes are applied, because the time before that adds nothing to the distance traveled
4. Only the distance covered before your foot reaches the brake pedal, and nothing after that
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Answer A: The distance covered while you perceive the hazard, the distance covered while you react, and the braking distance

Total stopping distance combines the ground covered while you notice the hazard, the ground covered while you move your foot to the brake, and the ground covered while the brakes slow the vehicle.
How does braking distance change if you double your speed?
1. It stays about the same
2. It becomes shorter because the brakes work harder
3. It grows exactly twice as long
4. It grows much more than twice as long
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Answer D: It grows much more than twice as long

Braking distance increases with the square of speed, so doubling speed roughly quadruples the distance needed to stop.
Why is following distance measured in seconds rather than in car lengths?
1. Because a time gap automatically grows with speed, while a fixed number of car lengths does not
2. Because the law expressly bans measuring the space ahead of you in car lengths
3. Because seconds are far easier to judge on the road than the length of the vehicle ahead of you
4. Because a gap measured in car lengths applies only to trucks and buses
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Answer A: Because a time gap automatically grows with speed, while a fixed number of car lengths does not

A gap counted in seconds keeps the same margin of reaction time at any speed, whereas a fixed number of car lengths becomes far too small as speed rises.
In which situation should you increase your usual following distance?
1. Only when the vehicle directly ahead of you is a passenger car rather than a truck or a bus
2. On wet roads, at night, in fog, when towing a trailer, or when following a motorcycle
3. Only when you are already driving below the posted speed limit for that road
4. Only when the road ahead is completely dry, straight and free of other traffic
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Answer B: On wet roads, at night, in fog, when towing a trailer, or when following a motorcycle

Reduced traction, reduced visibility, a heavier load and a vehicle that can stop faster than yours all require extra space to keep the same margin of safety.
You are approaching a sharp curve. When should you reduce your speed?
1. There is no need to slow at all as long as you stay inside your own lane
2. As you come out of the curve, once the road has straightened again
3. In the middle of the curve, where the sideways pull is strongest
4. Before you enter the curve, so you can accelerate gently through it
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Answer D: Before you enter the curve, so you can accelerate gently through it

Braking hard inside a curve uses up the traction that is already being demanded for cornering, so the slowing must be finished before you enter.
A vehicle in the lane beside you has stopped at a crosswalk. What should you do?
1. Change lanes and go around the stopped vehicle without slowing down
2. Pass carefully, since the part of the crosswalk in your own lane is clearly not blocked
3. Stop as well, because that driver may be yielding to a pedestrian you cannot see
4. Sound your horn to warn the other driver and continue past the crosswalk
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Answer C: Stop as well, because that driver may be yielding to a pedestrian you cannot see

The stopped vehicle hides the crosswalk from you, and passing it is a leading cause of collisions with pedestrians who are already crossing.
Is it acceptable to drive far below the flow of traffic on an open highway?
1. Yes, as long as you keep your hazard lights on
2. No, driving too slowly can obstruct traffic and create a hazard
3. Yes, any speed under the limit is always safe and lawful
4. Yes, because only exceeding the limit can be a violation
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Answer B: No, driving too slowly can obstruct traffic and create a hazard

Traffic that is much slower than the surrounding flow forces other drivers into sudden braking and unnecessary passing maneuvers, and impeding traffic is itself a violation.
You are about to descend a long steep grade. How should you control your speed?
1. Shift into neutral and coast down the grade so that fuel is saved
2. Hold steady pressure on the brake pedal all the way down so that the speed never rises at all
3. Build up speed at the top of the grade so that you can coast down the last part of it
4. Select a lower gear before starting down and use the brakes in firm, brief applications
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Answer D: Select a lower gear before starting down and use the brakes in firm, brief applications

Engine braking in a lower gear carries most of the load down the grade, while continuous brake pressure overheats the brakes and reduces their effectiveness.
You are entering a marked work zone. What should you expect?
1. That any flagger present controls only trucks and buses, not passenger vehicles
2. A reduced posted speed, narrowed or shifted lanes, and traffic that may stop suddenly
3. That all the lanes stay open until you actually reach the equipment and the workers
4. Normal speeds throughout, since the posted work zone signs apply only while workers are present
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Answer B: A reduced posted speed, narrowed or shifted lanes, and traffic that may stop suddenly

Work zones change the geometry of the road and can bring traffic to a halt without warning, so the posted work zone speed and increased following distance both apply.
What is the most common cause of rear-end collisions?
1. Driving with the headlights on during the day
2. Using the right lane instead of the left
3. Following too closely to stop in time
4. Braking too gently at intersections
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Answer C: Following too closely to stop in time

A driver who leaves too little space has no room to perceive, react and brake when the vehicle ahead slows, which is why space management prevents rear-end crashes.
How does higher speed affect the outcome of a crash?
1. It leaves less time to react and greatly increases the force of impact
2. It has no effect on the outcome once seat belts are properly worn
3. It only matters for vehicles that are heavier than an ordinary passenger car
4. It reduces the force of impact, because the collision itself is over sooner
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Answer A: It leaves less time to react and greatly increases the force of impact

Speed shortens the time available to avoid a hazard and raises the energy released in an impact, so both the likelihood and the severity of a crash increase.
The posted limit is 55 mph, but heavy traffic and rain make that speed unsafe. What does the law expect of you?
1. You may keep the posted speed, because the number on the sign is what is enforced
2. You must drive at least at the posted speed so that you do not hold up traffic
3. You may keep the posted speed as long as your headlights and wipers are working
4. You must slow to a speed that is safe for the conditions
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Answer D: You must slow to a speed that is safe for the conditions

The basic speed rule requires a speed that is reasonable for the traffic, weather and road, and that speed is often well below the posted maximum.

Source: dmv.ca.gov
Study tip. Rule out the options you know are wrong first. Two plausible answers are easier to choose between than four.
On dry pavement in good weather, what is the smallest following gap you should keep?
1. About three seconds behind the vehicle ahead
2. About one second, whatever speed you happen to be traveling at
3. One car length for every ten miles an hour of your speed
4. Half a second, which is the time an alert driver needs to react
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Answer A: About three seconds behind the vehicle ahead

Three seconds is the accepted minimum on dry roads in good visibility, and the gap should be longer in poor conditions.

Source: nhtsa.gov
You must stop for a train at a highway-rail crossing. Where should you stop?
1. As close to the rails as you can, so following drivers see the crossing early
2. Behind the stop line, gate or signal and well clear of the nearest rail
3. Level with the crossbuck sign, whatever distance that leaves to the rails
4. Wherever the vehicle comes to rest, since a train stays on its own rails
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Answer B: Behind the stop line, gate or signal and well clear of the nearest rail

Stop behind the stop line, gate or flashing-light signal and well clear of the nearest rail, because a train overhangs its track by several feet on each side.

Source: railroads.dot.gov
You are entering a marked school zone during the posted hours. What should you do?
1. Slow to the school zone limit and watch for children
2. Keep the normal street limit unless a crossing guard is standing in the road
3. Slow only when you can actually see children on the sidewalk or in the street
4. Sound your horn as you enter so that children near the curb hear you coming
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Answer A: Slow to the school zone limit and watch for children

The school zone limit applies throughout the posted hours, whether or not you can see any children at that moment.

Source: nhtsa.gov
How does a full load of passengers and luggage affect your braking?
1. It shortens the stopping distance, because the extra weight presses the tires down
2. It lengthens the stopping distance, so you should brake earlier
3. It has no effect at all, since the brakes work the same whatever the load
4. It only matters on a downgrade, where the load pushes the vehicle forward
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Answer B: It lengthens the stopping distance, so you should brake earlier

More weight means more energy to get rid of, so a loaded vehicle takes longer to stop and needs earlier, gentler braking.

Source: dmv.ca.gov
You are approaching the crest of a hill and cannot see the road beyond it. What should you do?
1. Hold your speed and stay in the middle of the road until you can see over
2. Speed up so that you spend as little time as possible on the blind section
3. Slow down and keep well to the right
4. Sound the horn twice so that any driver on the far side knows you are there
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Answer C: Slow down and keep well to the right

Beyond a blind crest there may be a stopped vehicle, a cyclist or an oncoming driver crossing the center line, so reduce speed and hold your own side.

Source: dmv.ca.gov
A driver moves into the space you were keeping ahead of you. What should you do?
1. Close up again quickly so that no other driver can take the same space
2. Flash your headlights until the other driver returns to the previous lane
3. Hold your speed, because the gap will open again by itself very soon
4. Ease off and rebuild the gap in front of you
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Answer D: Ease off and rebuild the gap in front of you

Losing a following gap is common in traffic; the answer is simply to drop back and recreate it rather than drive too close.

Source: dmv.ca.gov
What is the usual result of driving well above the flow of traffic on a typical trip?
1. A large time saving, which is why fast drivers arrive first on most journeys
2. Very little time saved, with much greater risk
3. A steady saving of about one minute for every mile that is driven
4. No change in risk, since crash risk depends only on the number of vehicles
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Answer B: Very little time saved, with much greater risk

Signals, traffic and short distances swallow the theoretical gain, while crash risk and crash severity both climb sharply with speed.

Source: nhtsa.gov
What counts as a complete stop at a stop sign?
1. Rolling slowly through the intersection while looking both ways carefully
2. Any speed under five miles an hour, which is slow enough to see cross traffic
3. The wheels stop turning before the stop line
4. A brief pause once the front of the vehicle has entered the intersection
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Answer C: The wheels stop turning before the stop line

A legal stop means the vehicle is no longer moving, made at the stop line or before entering the crosswalk or intersection.

Source: dmv.ca.gov
Why is smooth, early braking better than hard, late braking?
1. It keeps the brake pads cool enough to be used again within a few seconds
2. It is the only way to bring an antilock braking system into action properly
3. It shortens the total stopping distance more than any other technique does
4. It keeps you in control and gives the driver behind more warning
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Answer D: It keeps you in control and gives the driver behind more warning

Braking early and gently keeps the tires well within their grip and gives following drivers time to react to your brake lights.

Source: dmv.ca.gov
Which part of the space around your vehicle can you control best?
1. The space ahead of you
2. The space behind you, which you manage by watching the mirror
3. The space to your left, which other drivers are required to leave clear
4. The space to your right, which is protected by the edge of the road
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Answer A: The space ahead of you

You choose your own following distance, so the gap in front is the space you truly control and the one that gives you time to react.

Source: dmv.ca.gov
How do worn tires and worn brakes affect your ability to stop?
1. They have no effect until a warning lamp appears on the instrument panel
2. They shorten the stopping distance, because worn rubber grips the road harder
3. They lengthen the stopping distance, especially on a wet road
4. They only matter above highway speed, where air resistance becomes important
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Answer C: They lengthen the stopping distance, especially on a wet road

Worn tread cannot clear water and worn brakes cannot produce full force, so both stretch the distance needed to stop.

Source: nhtsa.gov
You turn from asphalt onto a loose gravel road. What should you do about your speed?
1. Keep it, because gravel gives the tires more grip than smooth asphalt does
2. Raise it slightly so that the tires ride over the top of the loose stones
3. Keep it, but brake harder than usual when you need to stop on the loose surface
4. Lower it, since grip is reduced and stopping takes longer
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Answer D: Lower it, since grip is reduced and stopping takes longer

Loose gravel gives far less grip than pavement, so speed must come down for both steering and stopping.

Source: dmv.ca.gov
You are towing a loaded trailer for the first time. How should you drive?
1. Slow earlier and keep a longer following gap
2. Exactly as you would without the trailer, since the brakes are unchanged
3. Closer to the vehicle ahead, so that other drivers cannot cut in between you
4. Faster on downgrades, using the weight of the trailer to carry you along
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Answer A: Slow earlier and keep a longer following gap

A trailer adds weight and length, so stopping takes longer and every maneuver needs more room and more warning.

Source: nhtsa.gov
A freeway sign shows a minimum speed limit. What does it require?
1. That you never drive slower than that speed, whatever the traffic conditions
2. That you keep up with it unless conditions make that unsafe
3. That trucks and buses only must reach at least that speed on the highway
4. That you move to the left lane whenever you drive slower than the number shown
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Answer B: That you keep up with it unless conditions make that unsafe

A minimum speed limit keeps very slow vehicles off the highway, but weather, traffic or a mechanical problem may make a lower speed necessary and lawful.

Source: mutcd.fhwa.dot.gov
You pass into a work zone with a reduced speed limit but you see no workers. What speed applies?
1. The normal highway limit, because the lower limit applies only while work goes on
2. The lower limit only when equipment is actually moving inside the work zone
3. Whatever your own judgment suggests, since the signs are advisory when it is quiet
4. The posted work zone limit, whether or not workers are present
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Answer D: The posted work zone limit, whether or not workers are present

A posted work zone speed limit is a regulatory limit in force at all times, and narrow lanes and uneven surfaces remain dangerous when nobody is working.

Source: highways.dot.gov
A train has just cleared a crossing that carries two sets of tracks. What should you do?
1. Cross at once, because a crossing is clear as soon as a train has gone by
2. Wait and look both ways for a second train
3. Cross only if the gates are still down, which holds back the traffic behind you
4. Sound the horn as you cross so that any approaching train can hear you coming
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Answer B: Wait and look both ways for a second train

A passing train hides a second train on the other track, so wait until the signals stop and you can see that both tracks are clear.

Source: railroads.dot.gov
You see brake lights several vehicles ahead of you in your lane. What is the best first step?
1. Change lanes at once, before the drivers behind react to the same brake lights
2. Sound the horn so the drivers between you and the problem pay attention
3. Ease off the gas and cover the brake pedal
4. Keep your speed until the vehicle directly ahead of you actually slows down
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Answer C: Ease off the gas and cover the brake pedal

Reacting to the trouble several vehicles ahead, rather than waiting for the car in front, cuts your reaction time and warns the driver behind you.

Source: dmv.ca.gov
Which statement best describes what the basic speed law requires of you?
1. That you always travel at exactly the number shown on the nearest posted sign
2. That you match the speed of the vehicle directly in front of you at all times
3. That you never drive faster than is reasonable and safe for the conditions
4. That you keep to the highest speed the traffic around you happens to be using
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Answer C: That you never drive faster than is reasonable and safe for the conditions

Nearly every state has a basic speed law that makes the conditions the real limit: weather, traffic, light and road surface can all require a speed well below the posted number.

Source: nhtsa.gov
You are leaving a freeway on an exit ramp posted with an advisory speed of 25 mph. Where should you slow to that speed?
1. In the deceleration lane, before you reach the curve of the ramp
2. Only after you have passed the sharpest part of the curve on the ramp
3. On the freeway itself, well before you reach the entrance to the exit lane
4. At the end of the ramp, where it joins the road you are turning onto
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Answer A: In the deceleration lane, before you reach the curve of the ramp

Slowing belongs in the deceleration lane so you arrive at the curve already at the advisory speed and do not hold up traffic still in the through lanes.

Source: dmv.ca.gov
You are on an entrance ramp joining a busy freeway. What should you do with your speed in the acceleration lane?
1. Keep it low and stop at the end of the lane until a very large gap appears
2. Hold a steady 25 mph and let the traffic in the right lane sort itself out
3. Speed up only after your front wheels are already inside the through lane
4. Build it up to about the speed of the traffic you are joining
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Answer D: Build it up to about the speed of the traffic you are joining

Merging works when your speed matches the traffic stream, because a large speed difference forces the drivers already on the freeway to brake or swerve.

Source: dmv.ca.gov
You have driven at 70 mph for an hour and then exit onto a town street. What is the common risk?
1. Your engine will be too hot to idle safely at the lower speed in town
2. Your sense of speed adapts, so 35 mph feels slow and you drive too fast
3. Your brakes will not work properly until they have cooled down completely again
4. Your tires lose air quickly whenever the road speed drops by a large amount
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Answer B: Your sense of speed adapts, so 35 mph feels slow and you drive too fast

After a long stretch at high speed the brain adapts, so town speeds feel unnaturally slow; check the speedometer instead of trusting the feeling.

Source: nhtsa.gov
For an alert driver, about how long is the reaction time once a hazard has been recognized?
1. About three quarters of a second
2. About one hundredth of a second
3. About five seconds under normal conditions
4. About fifteen seconds under normal conditions
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Answer A: About three quarters of a second

Reaction alone takes roughly three quarters of a second for an alert driver, and perception takes about as long again, so a second and a half of travel is added before the brakes bite.

Source: nhtsa.gov
What happens to your field of vision as your speed increases?
1. It widens, because the eyes take in more of the roadside at higher speed
2. It stays exactly the same, since vision does not depend on how fast you go
3. It narrows, so you notice less at the sides of the road
4. It improves at the sides but becomes worse straight ahead of the vehicle
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Answer C: It narrows, so you notice less at the sides of the road

The faster you travel, the more your useful field of view narrows toward the center, so a hazard coming from the side is seen late or missed altogether.

Source: nhtsa.gov
As speed rises, which part of the total stopping distance grows the fastest?
1. The distance covered while you are still perceiving the hazard ahead
2. The braking distance, which grows far faster than speed itself
3. The distance covered while you move your foot across to the brake pedal
4. All three parts grow by exactly the same amount at every road speed
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Answer B: The braking distance, which grows far faster than speed itself

Perception and reaction distances grow in step with speed, but braking distance grows roughly with the square of speed, so it dominates at higher speeds.

Source: nhtsa.gov
Travelling at about 55 mph on dry pavement, roughly how much room does an average car need to perceive, react and stop?
1. About 60 feet, or roughly the length of four parked cars
2. About 100 feet, or about the width of a residential street
3. About 500 feet, which is close to two full city blocks
4. About 300 feet, close to the length of a football field
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Answer D: About 300 feet, close to the length of a football field

Reaction distance plus braking distance at 55 mph comes to roughly 300 feet on good dry pavement, and considerably more on a wet or loose surface.

Source: nhtsa.gov
How much more energy must your brakes absorb if you double your speed?
1. The same amount, since the energy depends only on the weight of the vehicle
2. About half as much again, because the wheels are turning faster than before
3. Exactly twice as much, in direct proportion to the speed you are carrying
4. About four times as much, since energy rises with the square of speed
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Answer D: About four times as much, since energy rises with the square of speed

Kinetic energy grows with the square of speed, so twice the speed means about four times the energy and a far longer braking distance.

Source: nhtsa.gov
Why does a long downhill grade lengthen the distance you need to stop?
1. Because the tires lose air pressure steadily while the road runs downhill
2. Because the engine cannot deliver enough power to the braking system
3. Because gravity keeps pulling the vehicle forward as you brake
4. Because the steering becomes lighter and the front wheels turn more freely
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Answer C: Because gravity keeps pulling the vehicle forward as you brake

On a downgrade gravity works with the vehicle and against the brakes, so the same speed needs noticeably more distance than it would on level ground.

Source: dmv.ca.gov
You hold steady pressure on the brake pedal for the whole of a long descent. What is likely to happen?
1. The pedal becomes harder to press but the brakes keep their full strength
2. The brakes overheat and fade, so they slow you less and less
3. The parking brake engages by itself to help slow the vehicle down
4. The transmission shifts down on its own and holds your speed steady
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Answer B: The brakes overheat and fade, so they slow you less and less

Continuous braking heats the brakes until they fade and lose effectiveness; use a lower gear and short, firm applications instead.

Source: dmv.ca.gov
Why does a heavier vehicle need more room to stop than a light one from the same speed?
1. Because heavy vehicles are always fitted with smaller and weaker brakes
2. Because there is more mass in motion for the tires to slow down
3. Because the extra weight lifts the tires and reduces the grip they have
4. Because heavy vehicles are required by law to brake more gently than cars
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Answer B: Because there is more mass in motion for the tires to slow down

More mass means more energy at the same speed, and the brakes and tires need more distance to get rid of it.

Source: fmcsa.dot.gov
How does a wet road change the distance you need to stop?
1. It shortens it, because water cools the brakes and improves their bite
2. It leaves it unchanged as long as your tires are correctly inflated
3. It lengthens it, so you need a much bigger gap ahead
4. It changes only the reaction part of the total stopping distance
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Answer C: It lengthens it, so you need a much bigger gap ahead

Water between the tire and the road cuts grip, so braking distance grows and the gap that works on dry pavement is no longer enough.

Source: nhtsa.gov
Study tip. When two answers both seem legal, pick the one that is safer for everyone on the road. That is how most tests are written.
You come around a bend and find loose sand spread across your lane. What should you do?
1. Brake hard in the sand so that you are stopped before you reach the far side
2. Turn the wheel quickly from side to side to find the firm grip underneath
3. Accelerate through it so that the tires cut down to the solid surface below
4. Ease off the gas, avoid sudden braking or steering, and keep straight
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Answer D: Ease off the gas, avoid sudden braking or steering, and keep straight

Loose material acts like ball bearings under the tires; smooth inputs preserve what little grip remains, while sudden braking or steering breaks it.

Source: dmv.ca.gov
Freeway traffic ahead of you has come to a stop. Besides braking early, how can you warn the drivers behind you?
1. By steering from side to side within your lane so that your car is noticed
2. By switching on the hazard lights for a few seconds
3. By sounding the horn in short bursts until the traffic starts moving again
4. By switching on the high beams so the mirrors behind you light up brightly
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Answer B: By switching on the hazard lights for a few seconds

A short burst of hazard lights is a recognized way to tell following traffic that the queue ahead has stopped, and it carries much further back than brake lights. Some states restrict hazard lights on a moving vehicle, so use them only for the moment you are slowing.

Source: dmv.ca.gov
A driver is tailgating you. Why is it a bad idea to tap or stab the brakes to warn them?
1. Because your brake lights will then stay lit for several minutes afterwards
2. Because the vehicle behind you is legally allowed to follow that closely
3. Because it cuts the little space they have and can cause a crash
4. Because braking without signaling first is treated as an illegal maneuver
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Answer C: Because it cuts the little space they have and can cause a crash

Brake checking removes the small margin the tailgater has left and can provoke a collision; add space in front of you instead and let them pass.

Source: nhtsa.gov
On a narrow two-lane road a line of vehicles has built up behind you. What is the safe and courteous action?
1. Speed up well above the posted limit until the line of vehicles falls back
2. Move over onto the center line so that the drivers behind can see past you
3. Brake gently again and again until the drivers behind decide to pass you
4. Pull into a turnout or a safe wide spot and let them go by
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Answer D: Pull into a turnout or a safe wide spot and let them go by

A slow vehicle holding up a queue invites risky passing; using a turnout clears the road without anyone having to take a chance.

Source: dmv.ca.gov
You have stopped at a stop sign, but a parked truck blocks your view along the cross street. What should you do?
1. Creep forward slowly and stop again where you can see
2. Pull out quickly, so that you spend the least time in the path of traffic
3. Sound the horn once and then move out into the intersection as usual
4. Wait until a driver arrives behind you and signals that the road is clear
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Answer A: Creep forward slowly and stop again where you can see

When something blocks the view, a second stop closer to the intersection is the only safe way to see, and it must come before your vehicle enters the traffic lane.

Source: dmv.ca.gov
What is wrong with slowing to a crawl at a stop sign and then rolling on through?
1. Nothing at all, provided that you have already checked both ways for traffic
2. It wears out the brake pads much more quickly than a complete stop does
3. It is not a stop, and you may miss a pedestrian or cross traffic
4. It is permitted only where the intersection has no marked crosswalk lines
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Answer C: It is not a stop, and you may miss a pedestrian or cross traffic

A rolling stop is a violation and it also cuts short the moment you need in order to look carefully in each direction before entering.

Source: dmv.ca.gov
The red lights on a stopped school bus go out and the bus begins to move away. What should you do?
1. Pass at once on either side, because the stopping rule no longer applies
2. Move off slowly and keep watching for children near the road
3. Sound your horn to warn any children who might still be crossing the road
4. Wait where you are until the bus has gone completely out of your sight
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Answer B: Move off slowly and keep watching for children near the road

Children who have just left the bus may still be near the roadway or crossing behind it, so pull away gently and keep looking for them.

Source: nhtsa.gov
A driver is following you far too closely and you have a turn coming up. How should you slow down for it?
1. Brake at the last moment, so the driver behind has less time to close up
2. Signal early and slow gradually well before the turn
3. Speed up first so the driver falls back, and then brake as hard as you can
4. Wave the driver behind past you and then take the turn without signaling
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Answer B: Signal early and slow gradually well before the turn

Early signals and gentle braking give a tailgater the time and distance they have failed to leave for themselves.

Source: dmv.ca.gov
Why does even a small reduction in speed matter so much where people are walking?
1. Because pedestrians can hear a slower engine and will always step aside in time
2. Because the horn carries much further when the vehicle is moving slowly
3. Because low speeds switch on the automatic braking fitted to every vehicle
4. Because a pedestrian struck at a lower speed is far more likely to survive
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Answer D: Because a pedestrian struck at a lower speed is far more likely to survive

The chance that a pedestrian survives falls steeply as impact speed rises, so a few miles per hour can decide the outcome.

Source: nhtsa.gov
You enter a work zone at night where one lane is closed and a flagger is on duty. What is the safest approach?
1. Slow early, merge before the closure and be ready to stop
2. Keep your speed until the last cone and then merge quickly across
3. Switch to high beams so that you can read every sign in the work area
4. Stay in the closed lane and expect the workers to wave you around them
Show answer

Answer A: Slow early, merge before the closure and be ready to stop

Merging early at a reduced speed keeps the queue orderly and leaves you room to stop for equipment, workers or traffic that has halted ahead.

Source: ops.fhwa.dot.gov
On an unlit road, about how far ahead do high beams normally let you see?
1. About 100 feet, roughly the length of six parked cars end to end
2. About 1,000 feet, which is close to a quarter of a mile of road
3. About 50 feet, which is roughly the width of a two-lane street
4. About 350 to 500 feet ahead of the vehicle
Show answer

Answer D: About 350 to 500 feet ahead of the vehicle

High beams light roughly 350 to 500 feet of road and low beams far less, which is why night speeds have to be chosen around the beam, not the limit.

Source: nhtsa.gov
How does being tired change your total stopping distance?
1. It lengthens it, because you take longer to notice and react
2. It shortens it, because a tired driver brakes much harder than usual
3. It leaves it the same, since braking distance depends only on the vehicle
4. It changes only the braking part, not the time that you take to react
Show answer

Answer A: It lengthens it, because you take longer to notice and react

Fatigue stretches perception and reaction time, and every extra fraction of a second is added distance before the brakes even begin to work.

Source: nhtsa.gov
It is dark, it is raining and you are towing a trailer. How should you set your following gap?
1. Keep the usual three seconds, since the trailer has brakes of its own
2. Add extra seconds for each condition, well beyond three
3. Drop to two seconds so that the trailer does not swing out behind you
4. Use car lengths instead of seconds, counting one length per condition
Show answer

Answer B: Add extra seconds for each condition, well beyond three

Each factor that lengthens your stopping distance or shortens your view calls for another second or more, and they add up when several occur together.

Source: dmv.ca.gov
Apart from giving you room to stop, what else does a longer following gap do for you?
1. It lets the engine run at a lower and more economical speed setting
2. It allows you to use the horn instead of the brakes in an emergency
3. It gives the driver behind you permission to pass on the right side
4. It widens your view of the road and the traffic ahead
Show answer

Answer D: It widens your view of the road and the traffic ahead

Sitting further back lets you see past and around the vehicle in front, so hazards reach your eyes seconds earlier.

Source: dmv.ca.gov
May you exceed the posted speed limit in order to complete a pass?
1. Yes, as long as you return to the limit as soon as the pass is finished
2. Yes, but only on a road that has two or more lanes in your direction
3. No, the posted limit applies while you are passing too
4. Yes, provided the vehicle you are passing is traveling below the limit
Show answer

Answer C: No, the posted limit applies while you are passing too

The limit does not lift for passing; if you cannot complete the pass within it, there is not enough room and you should stay back.

Source: dmv.ca.gov
Children are playing close to the edge of a residential street. What is the right speed choice?
1. The posted limit exactly, because it already allows for children playing
2. Whatever speed keeps you moving with the vehicle in front of you
3. The posted limit minus five miles per hour, which is the national rule
4. Well below the limit, slow enough to stop for a sudden dash
Show answer

Answer D: Well below the limit, slow enough to stop for a sudden dash

Children can step out without warning, so the safe speed is the one that lets you stop within the distance you can see to be clear.

Source: nhtsa.gov
How far ahead should you normally be looking as you drive?
1. Just past the rear bumper of the vehicle that is directly in front of you
2. About two seconds ahead, which is the same as a safe following gap
3. About 12 to 15 seconds ahead, well beyond the vehicle in front
4. As far as the horizon, ignoring everything closer than a quarter of a mile
Show answer

Answer C: About 12 to 15 seconds ahead, well beyond the vehicle in front

Looking that far down the road lets you see a problem developing and slow smoothly, instead of discovering it in time only for hard braking.

Source: dmv.ca.gov
The road ahead is broken up with potholes and rough patches. What should you do?
1. Keep your speed and steer around each of the holes as you come to them
2. Speed up so that the tires skip across the tops of the holes
3. Slow down, since a hole hit at speed can wreck a tire or wheel
4. Move over into the oncoming lane, where the surface is usually smoother
Show answer

Answer C: Slow down, since a hole hit at speed can wreck a tire or wheel

A lower speed cuts the impact on tires, wheels and suspension and gives you time to choose a line through the rough surface.

Source: dmv.ca.gov
Another vehicle is passing you on a two-lane road. What should you do with your speed?
1. Hold your speed or ease off slightly to shorten the pass
2. Speed up, so that the two vehicles are side by side for less total time
3. Brake firmly so that the other driver can pull back in as soon as possible
4. Move onto the shoulder and stop there until the other vehicle is well past
Show answer

Answer A: Hold your speed or ease off slightly to shorten the pass

Speeding up strands the passing driver in the oncoming lane, while a steady speed or a slight lift lets the pass finish quickly and safely.

Source: dmv.ca.gov
You are following another vehicle down a long, steep grade. What should you do about the gap?
1. Close it up so that you do not have to use your own brakes as often
2. Keep exactly the same gap you would use on a flat road at that speed
3. Shorten it, because gravity slows both vehicles at the same rate anyway
4. Make it longer, because both of you need more room to stop
Show answer

Answer D: Make it longer, because both of you need more room to stop

Everything takes longer to stop on a downgrade, including the vehicle ahead, so the gap that works on the flat is no longer enough.

Source: dmv.ca.gov
Fog thickens until you can barely make out the vehicle ahead. What is the safest action?
1. Slow right down and, if needed, leave the road at a safe place
2. Keep your speed and follow the tail lights of the vehicle ahead of you
3. Stop in your lane and switch on the hazard lights until the fog clears
4. Turn on your high beams and hold the same speed as the other traffic
Show answer

Answer A: Slow right down and, if needed, leave the road at a safe place

In heavy fog the only safe speed may be very low, and if it drops below what the road allows, the answer is to pull well clear of the traffic lanes.

Source: nhtsa.gov
Traffic is backed up beyond a railroad crossing. When may you start across the tracks?
1. As soon as the vehicle in front of you has moved onto the tracks ahead
2. Only when there is room for your whole vehicle on the far side
3. At any time, because the crossing signals will warn you before a train
4. Once you have stopped on the tracks and looked carefully in both directions
Show answer

Answer B: Only when there is room for your whole vehicle on the far side

Never enter a crossing you cannot clear; a vehicle stopped on the tracks in a queue has nowhere to go if the signals start.

Source: railroads.dot.gov
Halfway through a curve you realize you are going too fast. What is the best response?
1. Brake as hard as you can while holding the steering wheel dead straight
2. Steer sharply toward the inside edge and hold the speed you already have
3. Ease off the gas gently and look where you want to go
4. Pull the parking brake to tighten the line the vehicle is taking
Show answer

Answer C: Ease off the gas gently and look where you want to go

Easing off transfers a little weight to the front tires without upsetting the balance, and looking through the curve keeps your steering smooth.

Source: dmv.ca.gov
You are first in the queue at a red light with a marked crosswalk. Where should your vehicle stop?
1. Behind the stop line, so that the crosswalk stays clear
2. With the front wheels resting on the near edge of the crosswalk markings
3. Just past the crosswalk, from where you can see the cross street better
4. Anywhere before the far side of the intersection you are waiting at
Show answer

Answer A: Behind the stop line, so that the crosswalk stays clear

Stopping short of the line keeps the crosswalk usable for people on foot and keeps your vehicle out of the path of turning traffic.

Source: dmv.ca.gov
Which surfaces usually offer less grip than the pavement around them when wet?
1. Fresh asphalt laid during the most recent resurfacing of the road
2. Painted markings, metal plates and bridge decks
3. Concrete sections on the approach to a signaled intersection
4. Gravel shoulders that have been rolled flat by heavy machinery
Show answer

Answer B: Painted markings, metal plates and bridge decks

Paint, steel and bridge decks all shed grip when wet or cold, so brake before you reach them rather than on top of them.

Source: nhtsa.gov