Speed for curves, sight distance, traffic, downgrades and work zones

Review questions with answers

1. A truck with a high center of gravity takes a curve at the posted speed limit. What can happen?
   1. Nothing; the posted speed is always safe
   2. The brakes will lock automatically
   3. It can roll over
   4. The engine will overspeed
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   It can roll over

   Tests show high-CG trucks can roll over at the posted curve speed.

2. When should you slow down for a curve?
   1. Before you enter the curve
   2. In the middle of the curve
   3. As you exit the curve
   4. Only if the road is wet
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   Before you enter the curve

   Slow before the curve; braking in a curve can lock wheels and cause a skid.

3. Why is braking in a curve dangerous?
   1. It overheats the engine
   2. It wears the tires evenly
   3. It makes the vehicle go faster
   4. It is easier to lock the wheels and cause a skid
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   It is easier to lock the wheels and cause a skid

   Braking in a curve makes wheel lockup and skids more likely.

4. Taking a curve too fast can cause two things. One is a skid off the road. What is the other?
   1. A blowout
   2. A rollover
   3. A stalled engine
   4. Brake fade
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   A rollover

   If the tires keep traction, the vehicle may roll over instead of skidding.

5. While in a curve, you should be in a gear that lets you:
   1. Coast in neutral
   2. Brake hard if needed
   3. Accelerate slightly
   4. Shift up in the middle of the curve
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   Accelerate slightly

   Slight acceleration through the curve helps you keep control.

6. You should always be able to stop:
   1. Within the distance you can see ahead
   2. Within 100 feet
   3. Within two seconds
   4. Before the next exit
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   Within the distance you can see ahead

   Drive at a speed that lets you stop within your sight distance.

7. At night, when you must use low beams, you should:
   1. Drive closer to the center line
   2. Follow other vehicles more closely
   3. Keep the same speed as with high beams
   4. Slow down, because you cannot see as far
   Show answer

   Slow down, because you cannot see as far

   Low beams show less of the road, so reduce speed.

8. In heavy traffic, the safest speed is usually:
   1. Slightly faster than traffic
   2. The speed of the other vehicles, if legal and safe
   3. 10 mph below traffic
   4. The posted maximum, always
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   The speed of the other vehicles, if legal and safe

   Vehicles moving the same direction at the same speed are unlikely to hit each other.

9. In some states, the speed limit for trucks and buses can be lower than for cars by as much as:
   1. 5 mph
   2. 25 mph
   3. 15 mph
   4. 30 mph
   Show answer

   15 mph

   The difference can be as much as 15 mph; take extra care changing lanes or passing.

10. Why is driving faster than the flow of traffic a poor choice?
    1. You save little time, pass more often, raise crash risk and get more tired
    2. It always saves a lot of time
    3. It reduces fuel use
    4. It keeps tailgaters away
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    You save little time, pass more often, raise crash risk and get more tired

    Speeding saves little time; constant passing and fatigue raise crash risk.

11. On a downgrade, your speed should not be too fast for all of these EXCEPT:
    1. The total weight of vehicle and cargo
    2. The length and steepness of the grade
    3. Road conditions and weather
    4. Your delivery schedule
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    Your delivery schedule

    Choose speed for weight, grade length, steepness, road conditions and weather — not your schedule.

12. What should be the principal way of controlling your speed on a downgrade?
    1. The service brakes
    2. The braking effect of the engine
    3. The parking brake
    4. Shifting to neutral
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    The braking effect of the engine

    Use engine braking as the main control; save the service brakes.

13. Engine braking is greatest when:
    1. The engine is at idle in a high gear
    2. The clutch is pushed in
    3. The engine is near governed rpm and the transmission is in a lower gear
    4. The vehicle is in neutral
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    The engine is near governed rpm and the transmission is in a lower gear

    Engine braking is strongest near governed rpm in the lower gears.

14. A sign on a downgrade shows “Maximum Safe Speed 35.” What should you do?
    1. Never exceed 35 mph
    2. Go up to 10 mph over if the road is dry
    3. Ignore it if your load is light
    4. Treat it as the minimum speed
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    Never exceed 35 mph

    Never exceed a posted speed limit or Maximum Safe Speed sign.

15. When should you shift to a low gear for a long downgrade?
    1. Halfway down
    2. When the brakes start to fade
    3. At the bottom
    4. Before starting down the grade
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    Before starting down the grade

    Get into a low gear before the downgrade begins.

16. What causes the most injuries and deaths in roadway work zones?
    1. Poor lighting
    2. Speeding traffic
    3. Loose gravel
    4. Lane closures
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    Speeding traffic

    Speeding traffic is the top cause of work-zone injury and death.

17. In a long work zone, a worker is standing close to the road. You should:
    1. Keep the posted speed exactly
    2. Sound your horn and keep going
    3. Slow down even further
    4. Change lanes quickly toward the worker
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    Slow down even further

    Decrease speed even more when a worker is close to the roadway.

18. In long stretches of road construction, a common danger is:
    1. Letting your speed creep up
    2. Driving too slowly
    3. Using low beams
    4. Following the posted signs
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    Letting your speed creep up

    Watch the speedometer and do not let speed creep up.

19. Gravity makes a vehicle's speed decrease on downgrades.
    1. True
    2. False
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    False

    False. Gravity makes speed increase on downgrades.