Lesson 5 of 32 · Pennsylvania PennDOT Knowledge Test · Free

Drive Wisely: Matching Speed to Road Conditions

Adjust speed for traffic, visibility, and grip to keep stopping distances safe.

Drive Wisely: Matching Speed to Road Conditions: practice questions and answers

These are the 16 quiz questions from this lesson for the Pennsylvania PennDOT Knowledge Test, with the correct answers and explanations. Try the quiz above first, then open a question to check yourself.

1

When bad weather reduces visibility, you should:
  1. Increase the space between you and the vehicle ahead. ✓ Correct
  2. Accelerate to leave the roadway faster.
  3. Travel in the lane nearest to oncoming vehicles.
  4. Turn on hazard lights and maintain current speed.

Correct answer: A. Increase the space between you and the vehicle ahead.

Because your visibility is limited and the road surface is likely slippery, you need a much larger "safety cushion"; increasing your following distance gives you the extra time required to react if the car ahead brakes suddenly.

2

In fog or smoke, you should:
  1. Keep a four-second gap at posted speed.
  2. Increase following distance and reduce speed. ✓ Correct
  3. Use high beams and keep the same following distance.
  4. Stay in the lane nearest to oncoming traffic.

Correct answer: B. Increase following distance and reduce speed.

As visibility drops, your ability to see and react to hazards ahead decreases. Increasing your following gap and reducing your speed gives you the extra time and space needed to respond safely to whatever appears out of the fog.

3

On a 65 mph freeway where traffic moves at 70 mph, your legal maximum speed is:
  1. At 70 mph to match the flow of traffic.
  2. No faster than 65 mph. ✓ Correct
  3. Somewhere between 65 mph and 70 mph.
  4. Up to 70 mph if you are passing another vehicle.

Correct answer: B. No faster than 65 mph.

The posted speed limit is the law. Regardless of how fast others are driving, exceeding 65 mph is a violation.

4

If you drive at a speed slower than the flow of traffic, you will most likely:
  1. Improve safety by forcing others to slow down.
  2. Impede or block the normal movement of traffic. ✓ Correct
  3. Have better visibility of road signs and exits.
  4. Save fuel and reduce the wear and tear on your vehicle.

Correct answer: B. Impede or block the normal movement of traffic.

Driving significantly slower than the surrounding cars makes you a "moving roadblock"; this disrupts the natural flow, frustrates other drivers, and often leads to dangerous "weaving" and aggressive passing maneuvers by those behind you.

5

When passing a row of parked vehicles, you should:
  1. Speed up to pass quickly and minimize the time spent in the danger zone.
  2. Be ready for a person or vehicle to suddenly move into your lane. ✓ Correct
  3. Assume that all other drivers and pedestrians will yield to you.
  4. Honk your horn continuously to alert anyone who might be behind the parked cars.

Correct answer: B. Be ready for a person or vehicle to suddenly move into your lane.

Parked cars act as a visual screen for "hidden hazards." By staying alert and keeping a foot near the brake, you are prepared for the most common dangers: a car pulling out of a space or a pedestrian stepping out from between the vehicles.

6

When your view of the road is partially blocked, you should:
  1. Maintain speed if you know the road well.
  2. Always slow down. ✓ Correct
  3. Follow the vehicle ahead closely to guide you.
  4. Only worry about visibility at night or in bad weather.

Correct answer: B. Always slow down.

Any time your view is partially obstructed, whether by a curve, a hill, a large vehicle, or poor weather, slowing down gives you the extra time and space to react to whatever might be hidden from view.

7

Speed limits are lower in residential and school zones to:
  1. To reduce traffic congestion.
  2. To avoid confusion at intersections.
  3. To give drivers more time to react. ✓ Correct
  4. To make it easier for police to issue tickets.

Correct answer: C. To give drivers more time to react.

Kids are small and unpredictable. Dropping to 15 mph gives you those extra seconds to slam on the brakes if someone suddenly darts into the road.

8

At what point during a rainfall are roads slippery on a hot day?
  1. Immediately after it has stopped raining.
  2. For the first 10-15 minutes. ✓ Correct
  3. When it has been raining for a few hours.
  4. Only once the sun dries the road.

Correct answer: B. For the first 10-15 minutes.

On a hot day, oil, dust, and debris accumulate on the road surface. When rain first falls, it mixes with all of that to create an incredibly slick layer. After a few minutes the rain washes it away and grip gradually improves.

9

Which of the following statements about speed adjustments on different road conditions is INCORRECT?
  1. Reduce your speed by 5 to 10 mph on wet roads.
  2. Halve your speed on roads covered with packed snow.
  3. Slow down to 5 mph on icy roads.
  4. Maintain the same speed regardless of road conditions. ✓ Correct

Correct answer: D. Maintain the same speed regardless of road conditions.

Maintaining the same speed regardless of road conditions directly violates the Safe Speed Law and is one of the most dangerous things a driver can do. Every change in road surface requires a corresponding adjustment in speed.

10

Crashes are more likely to occur when:
  1. All vehicles are traveling at about the same speed.
  2. One lane of traffic is traveling faster than the other lanes.
  3. One vehicle is traveling faster or slower than the flow of traffic. ✓ Correct
  4. Traffic density is high and vehicles are close together.

Correct answer: C. One vehicle is traveling faster or slower than the flow of traffic.

A single vehicle moving significantly faster or slower than surrounding traffic creates unpredictable speed differentials that force other drivers to react suddenly, dramatically increasing the risk of a collision.

11

When the road surface is wet or icy, you should:
  1. Pump your brakes repeatedly to test the road surface.
  2. Slow down. ✓ Correct
  3. Drive at the posted speed limit.
  4. Maintain your usual speed if your vehicle has all-wheel drive.

Correct answer: B. Slow down.

Wet and icy surfaces dramatically reduce traction and increase stopping distances. Slowing down is the most effective way to stay in control and give yourself enough space to react safely.

12

On slippery roads, you should:
  1. Brake hard to prevent sliding.
  2. Maintain speed to keep the vehicle stable.
  3. Increase your following distance. ✓ Correct
  4. Shift to a lower gear and keep your usual following distance.

Correct answer: C. Increase your following distance.

Slippery roads mean longer stopping distances, so increasing your following distance gives you the extra space needed to brake gently and gradually without losing control.

13

What does this sign mean?
Illustration for: What does this sign mean?
  1. School zone ahead. ✓ Correct
  2. Pedestrian crossing ahead.
  3. Playground zone ahead.
  4. Two women returning from a shopping trip.

Correct answer: A. School zone ahead.

The pentagon shape, yellow color, and two figures walking together identify this as a school zone warning sign. It alerts drivers to slow down and watch carefully for children crossing the road.

14

This sign means:
Illustration for: This sign means:
  1. Pedestrians only
  2. Intersection ahead
  3. Hiking trails ahead
  4. School crossing ahead ✓ Correct

Correct answer: D. School crossing ahead

This pentagon-shaped sign is very similar to a school zone sign. However, notice the lines painted under the people in the image; these indicate the actual location of the school crossing.

15

When passing a pedestrian on the roadway with oncoming traffic, you should:
  1. Keep speed and assume the oncoming driver will yield.
  2. Honk to force the pedestrian aside.
  3. Straddle the center line to give the pedestrian space.
  4. Slow down and wait for oncoming traffic to pass first. ✓ Correct

Correct answer: D. Slow down and wait for oncoming traffic to pass first.

By slowing down and letting the oncoming vehicle pass, you create the space needed to move over and give the pedestrian a wide berth. This "separates the hazards" so you handle each one individually.

16

Why are minimum speed limit signs posted on freeways?
  1. To allow drivers to travel at any speed below the maximum limit.
  2. To encourage drivers to exceed the posted speed limit.
  3. To keep traffic flowing smoothly and safely. ✓ Correct
  4. To give priority to slow-moving vehicles.

Correct answer: C. To keep traffic flowing smoothly and safely.

This is the correct answer. Minimum speed limits reduce the need for constant passing and lane-weaving. By keeping everyone within a specific "speed window," traffic remains predictable, merging is easier, and the risk of rear-end collisions is significantly lowered.

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