SSC JE Exam - traffic engineering surveys speed flow density intersections signals road safety Question Bank with Options

1. Which survey is crucial for planning public transportation routes and services?

A) Traffic volume study

B) Speed study

C) Origin-destination study

D) Parking study

2. What is the 'protected-permissive' phase in traffic signal terminology?

A) A phase where all movements are protected

B) A phase where a left-turn movement has a protected green arrow followed by a permissive green ball

C) A phase with only a permissive green ball

D) A phase with an all-red clearance

3. The relationship where flow decreases as density increases beyond a certain point is characteristic of:

A) Free-flow conditions

B) Congested traffic conditions

C) Stable traffic flow

D) Low-density traffic

4. What is the main advantage of using automatic traffic recorders (ATRs) over manual counts?

A) They can record turning movements

B) They can operate continuously and unattended for long periods

C) They provide detailed information on trip purpose

D) They are less expensive to deploy

5. Which of the following is a proactive approach to road safety?

A) Investigating accidents after they occur

B) Implementing traffic calming measures

C) Analyzing accident data

D) Providing emergency services

6. The 'capacity reduction factor' is used in intersection analysis to account for:

A) Vehicle acceleration

B) The effect of heavy vehicles and grades

C) Pedestrian activity

D) Traffic signal timing

7. What does a 'traffic stream model' aim to describe?

A) The physical characteristics of vehicles

B) The macroscopic behavior of traffic flow, speed, and density

C) The design of traffic signals

D) The road network layout

8. What is the 'minimum headway'?

A) The time between the start of one vehicle and the start of the next

B) The shortest time interval between two consecutive vehicles passing a point

C) The time it takes for a vehicle to pass a point

D) The time a vehicle waits at a red light

9. Which type of survey is most useful for understanding the modal split of commuters?

A) Traffic volume count

B) Turning movement count

C) Home interview survey or travel diary

D) Speed study

10. In the context of traffic signals, what is 'phase'?

A) The entire cycle of signal indications

B) A specific movement or group of compatible movements given the right-of-way

C) The duration of the green light

D) The time allocated for pedestrians

11. What does the Highway Capacity Manual (HCM) provide?

A) A list of traffic laws

B) Methodologies for analyzing the capacity and level of service of various highway facilities

C) Traffic signal timing plans

D) Road safety guidelines

12. Which tool is commonly used for detailed analysis of traffic operations at complex intersections?

A) Manual traffic counter

B) Speed radar

C) Traffic simulation software (e.g., VISSIM, CORSIM)

D) Enoscope

13. What is the primary purpose of 'traffic rationing' or 'demand management' strategies?

A) To increase road capacity

B) To reduce traffic demand during peak periods

C) To increase vehicle speeds

D) To improve traffic flow efficiency

14. A 'travel time study' is used to determine:

A) The number of vehicles on a road

B) The time taken to travel between two points

C) The density of traffic

D) The capacity of an intersection

15. What is the 'space mean speed'?

A) The average speed of all vehicles passing a point at a given instant

B) The average speed of vehicles over a specific time interval

C) The arithmetic mean of the speeds of vehicles at a given instant over a given length of roadway

D) The speed limit on a road

16. Which of the following is a qualitative measure of traffic flow?

A) Vehicles per hour

B) Density (vehicles/km)

C) Level of Service (LOS)

D) Average speed (km/hr)

17. What is the primary function of a 'traffic simulation model'?

A) To directly measure traffic flow

B) To replicate traffic operations and test different scenarios

C) To set traffic signal timings

D) To count vehicles

18. The 'capacity of an intersection' is defined as:

A) The maximum number of vehicles that can pass through the intersection in an hour

B) The number of lanes at the intersection

C) The average speed of vehicles at the intersection

D) The density of vehicles approaching the intersection

19. Which survey method is best for determining the economic impact of a new road?

A) Traffic volume count

B) Origin-destination study

C) Economic impact study (often involving surveys of businesses and residents)

D) Speed study

20. What is the 'lost time' in traffic signal phasing?

A) The time when the signal is red

B) The time taken to accelerate from a stop and decelerate to a stop

C) The duration of the yellow light

D) The time when no vehicles are present

21. Which type of traffic signal control is most responsive to real-time traffic demand?

A) Pre-timed signals

B) Actuated signals

C) Coordinated signals

D) Fixed-time signals

22. What is the purpose of a 'cordon line' in traffic surveys?

A) To measure vehicle speed

B) To count traffic entering or leaving a defined area

C) To determine traffic density

D) To assess road surface condition

23. A 'speed-density relationship' typically shows that as density increases, speed:

A) Increases linearly

B) Decreases

C) Remains constant

D) Increases exponentially

24. What is the main goal of implementing traffic calming measures?

A) To increase traffic speed

B) To reduce traffic volume

C) To improve road safety by reducing speed and volume

D) To optimize signal timings

25. Which of the following is a primary cause of traffic congestion?

A) Excessive road capacity

B) Low traffic demand

C) Bottlenecks and insufficient capacity

D) Predictable traffic flow

26. What does a 'peak hour factor' (PHF) represent?

A) The ratio of average flow rate to the maximum flow rate in 15-minute intervals within the peak hour

B) The total traffic volume during the peak hour

C) The average speed during the peak hour

D) The density of traffic during the peak hour

27. A traffic study involving placing observers at specific points to record vehicle characteristics and driver actions is known as a:

A) License plate survey

B) Manual traffic count

C) Enoscope study

D) Home interview survey

28. Which factor is NOT typically considered when determining the capacity of a highway segment?

A) Number of lanes

B) Lane width

C) Shoulder width

D) Average trip length

29. What is the 'clearance interval' in a traffic signal cycle?

A) The green light phase

B) The yellow light phase

C) The all-red phase, providing time for vehicles to clear the intersection

D) The pedestrian crossing time

30. In traffic signal timing, what is 'cycle length'?

A) The duration of a single green light phase

B) The total time for all phases to occur once

C) The time between two consecutive green lights for the same approach

D) The duration of the yellow light

31. What is the primary purpose of a 'turning movement count' at an intersection?

A) To measure the speed of vehicles

B) To count vehicles making left, right, and through movements

C) To determine traffic density

D) To assess road safety

32. The 'level of service' (LOS) concept in traffic engineering is used to:

A) Count the number of vehicles

B) Measure traffic density

C) Describe operational conditions and quality of traffic flow

D) Determine intersection capacity

33. Which type of survey is most effective for understanding driver behavior and attitudes towards safety?

A) Traffic volume count

B) Speed study

C) Attitude surveys or driver questionnaires

D) Origin-destination study

34. What is a 'saturation flow rate' at an intersection approach?

A) The actual flow rate observed during peak hours

B) The maximum flow rate achievable under ideal conditions with a continuous demand

C) The average flow rate over a day

D) The flow rate during off-peak hours

35. Which of the following is a common method for measuring spot speed?

A) License plate matching

B) Radar gun or pneumatic tubes

C) Home interviews

D) Expansion factors

36. What does the 'headway' refer to in traffic flow?

A) The distance between the front of two consecutive vehicles

B) The time interval between the front of two consecutive vehicles passing a point

C) The total length of a vehicle

D) The speed of a single vehicle

37. Which type of traffic signal controller adjusts signal timing based on detected vehicle presence?

A) Pre-timed controller

B) Actuated controller

C) Manual controller

D) Fixed-time controller

38. The 'jam density' is the density at which:

A) Flow is maximum

B) Speed is zero and density is maximum

C) Speed is average

D) Flow is minimum

39. What is the primary purpose of a roadside interview survey?

A) To measure vehicle speeds

B) To collect information on trip purpose, mode of travel, and O-D data

C) To count traffic volume

D) To assess road surface condition

40. The maximum flow rate that can be achieved at a specific location under prevailing conditions is known as:

A) Traffic density

B) Traffic capacity

C) Average speed

D) Saturation flow

41. Which of the following is NOT a direct measure of traffic flow?

A) Vehicles per hour

B) Vehicles per day

C) Vehicles per kilometer

D) Vehicles per minute

42. Road safety audits are primarily conducted to:

A) Increase traffic flow efficiency

B) Identify potential hazards and recommend safety improvements

C) Measure traffic volume and density

D) Optimize traffic signal timings

43. What is the critical lane in the context of intersection analysis?

A) The lane with the highest traffic volume

B) The lane that controls the capacity of the intersection approach

C) The lane used by the majority of vehicles

D) The lane with the shortest approach length

44. Which type of traffic signal control is typically used at low-volume intersections with predictable traffic patterns?

A) Actuated signals

B) Pre-timed signals

C) Coordinated signals

D) Volume-density signals

45. What is the purpose of a speed and delay study?

A) To measure the total traffic volume on a route

B) To identify bottlenecks and causes of delay

C) To determine the capacity of intersections

D) To record the origin and destination of vehicles

46. The relationship between speed, flow, and density is often represented by the fundamental equation: Flow = Speed × Density. If flow is 2000 vehicles/hour and density is 50 vehicles/km, what is the average speed?

A) 10 km/hr

B) 40 km/hr

C) 50 km/hr

D) 100 km/hr

47. Which survey method is most suitable for determining the origin and destination of traffic?

A) Manual traffic counts

B) Automatic traffic recorders

C) License plate surveys

D) Home interview surveys

48. What does 'traffic density' represent in traffic engineering?

A) The total number of vehicles on a road segment

B) The rate at which vehicles pass a point

C) The number of vehicles occupying a given length of roadway at a specific instant

D) The average speed of vehicles on a highway

49. Which of the following is the primary objective of a traffic volume study?

A) To determine average travel speed of vehicles

B) To measure the spacing between vehicles

C) To count the number of vehicles passing a point over a period of time

D) To assess the level of service at an intersection

traffic engineering surveys speed flow density intersections signals road safety - Question Bank