Transportation Engineering Questions and Answers Part-8

1. What does PIEV mean?
a) Perception, Imitation, Environment, and Volition
b) Perception, Identification, Environment, and Volition
c) Perception, Identification, Emotion, and Volition
d) Perception, Identification, Emotion, and Violation

Answer: c
Explanation: PIEV means Perception, Identification, Emotion, and Volition. This essentially means that a driver requires time to see and hear the action on the road and process it and act according to the circumstances on the road.

2. What are the factors that affect PRT?
a) Age, presence of alcohol and drugs, road rage, walking speed
b) Age, presence of alcohol and drugs, fatigue, complexity of reactions
c) Age, presence of alcohol and drugs, fatigue, size of obstruction
d) Age, presence of alcohol and drugs, fatigue, type of pavement

Answer: b
Explanation: The factors that affect PRT are age, presence of alcohol and drugs, fatigue and complexity of reactions. Expectancy is also a significant factor affecting PRT i.e. drivers will react more quickly to circumstances they expect to stumble upon.

3. What is the Perception Reaction Time for braking on highways?
a) 1 second
b) 2.5 seconds
c) 3.5 seconds
d) 3 seconds

Answer: b
Explanation: The Perception Reaction Time (PRT) for braking on highways is 2.5 seconds. The Perception Reaction Time (PRT) for reaction time to traffic signals is 1 second. These recommendations are specified by AASHTO.

4. The initial speed of the vehicle is 80 kmph. What is the reaction distance?
a) 45.5 m
b) 55.2 m
c) 55.6 m
d) 22.24 m

Answer: c
Explanation: d = 0.278 S.t
here,
d = reaction distance
S = initial speed of vehicle, kmph
t = reaction time, s = 2.5 seconds
d = 0.278 X 80 X 2.5 = 55.6 m

5. A vehicle travels at a speed of 60 kmph. The driver then sees a stopped car on the road ahead. How far will the driver’s vehicle travel before the driver’s foot reach the brake?
a) 41.7 m
b) 40 m
c) 31.2 m
d) 45 m

Answer: a
Explanation: d = 0.278 S.t
here,
d = reaction distance
S = initial speed of vehicle, kmph
t = reaction time, s = 2.5 seconds
d = 0.278 X 60 X 2.5 = 41.7 m

6. The driver notices a red traffic signal towards the front. The vehicle moves 11m before he can observe and apply brakes on the vehicle. At what speed the vehicle was moving?
a) 30 kmph
b) 40 kmph
c) 50 kmph
d) 60 kmph

Answer: b
Explanation: d = 0.278 S.t
here,
d = reaction distance
S = initial speed of vehicle, kmph
t = reaction time, s = 1 seconds for reaction on a traffic signal
d = 0.278 X S X 1
11 = 0.278 X S X 1
S = 11/0.278 = 39.5 kmph = 40 kmph (approx.)

7. What is the AASHTO recommendation for a PRT for stops on rural roads where collision avoidance maneuver is required?
a) 9.1 seconds
b) 10 seconds
c) 8 seconds
d) 3 seconds

Answer: d
Explanation: The AASHTO recommendation for a PRT for stops on rural roads where collision avoidance maneuver is required is 3 seconds. It is 9.1 seconds for urban roads.

8. Which of the following is not a category of expectancy?
a) Continuity
b) Event
c) Temporal
d) Complexity of reaction

Answer: d
Explanation: Complexity of reaction is not a category of expectancy but it is one of the factors affecting PRT. Continuity, Event, and Temporal are the types of expectancy.

9. A driver with a perception-reaction time of 2.5s is driving with a speed of 75 kmph. He observes an accident on the road ahead. Workout the distance the vehicle will travel before the driver applies brakes.
a) 49 m
b) 52 m
c) 50 m
d) 53 m

Answer: b
Explanation: d = 0.278 S.t
here,
d = reaction distance
S = initial speed of vehicle, kmph
t = reaction time, s = 2.5 seconds
d = 0.278 X S X 2.5
d = 0.278 X S X 2.5
d = 52.125 m = 52 m (approx.)

10. What is the AASHTO recommendation for a PRT on urban roads where collision avoidance requires speed, path and direction changes?
a) 14 to 14.5 seconds
b) 10.2 to 11.2 seconds
c) 12.1 to 12.9 seconds
d) 9.1 to 9.9 seconds

Answer: a
Explanation: The AASHTO recommendation for a PRT on urban roads where collision avoidance requires speed, path, and direction changes is 14 to 14.5 seconds. It is 10.2 to 11.2 seconds for rural roads and 12.1 to 12.9 seconds for suburban roads.