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Question 1. In Synchro, which map source provides a georeferenced aerial image that can be directly imported without needing a separate coordinate file? A) OpenStreetMap tiles B) Bing Maps imagery C) PDF scanned maps D) Hand-drawn sketches Answer: B Explanation: Bing Maps imagery is a built-in georeferenced source; Synchro can import it and automatically align latitude/longitude. Question 2. When scaling a CAD background file, which parameter must be entered to ensure correct real-world dimensions? A) Map projection code B) Scale factor (e.g., 1:100) C) Image resolution (dpi) D) Layer color index Answer: B Explanation: The scale factor converts CAD units to real-world distances, allowing accurate placement of links and nodes. Question 3. Which node type in Synchro automatically applies a “yield” control to all approaches? A) Signalized B) Unsignalized C) Roundabout D) Crossover
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Answer: C Explanation: Roundabouts are modeled as yield-controlled intersections; all entering traffic yields to circulating flow. Question 4. In link geometrics, a “pocket length” is most important for which traffic movement? A) Through traffic B) Right-turn only lane C) Exclusive left-turn lane D) Pedestrian crossing Answer: C Explanation: Pocket length defines the distance needed for vehicles to complete an exclusive left-turn before merging back. Question 5. The “Peak Hour Factor” (PHF) of 0.92 indicates what about the traffic flow during the peak hour? A) Flow is 92 % of the design capacity B) Traffic is highly variable, with peaks exceeding average by 8 % C) Saturation flow should be reduced by 8 % D) The peak hour is 92 % as long as the design hour Answer: B Explanation: PHF = (Total volume in peak hour) / (4 × 15-minute peak volume); a value <1 shows variability, with the 15-minute peak exceeding the average by about 8 %. Question 6. Which saturation flow rate is most appropriate for a lane with a high proportion of heavy trucks? A) 1900 veh/hr/ln
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A) Pre-timed B) Fixed-cycle C) Actuated D) Semi-actuated Answer: C Explanation: Actuated controllers use detectors to extend green phases when demand is present. Question 10. In Synchro, the “Minimum Green” interval is: A) The shortest green time allowed for any phase, regardless of demand B) The average green time across all phases C) The green time required for pedestrian clearance D) The time between yellow and red clearance Answer: A Explanation: Minimum Green sets a lower bound to ensure each movement receives enough green, even with low demand. Question 11. According to MUTCD, the minimum “Walk” interval for a pedestrian crossing with a 20-ft crossing length and a 4 mph walking speed is: A) 5 seconds B) 7 seconds C) 9 seconds D) 11 seconds Answer: C Explanation: Walk time = crossing length / walking speed = 20 ft / (4 mph ≈ 352 ft/min) ≈ 3.4 seconds; MUTCD adds a safety factor,
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resulting in a minimum of 7 seconds, but Synchro defaults to 9 seconds for 20 - ft crossings. Question 12. Which detector placement is recommended for a lane-specific actuation on a through movement? A) At the stop line B) 15 ft upstream of the stop line C) 30 ft upstream of the stop line D) 45 ft upstream of the stop line Answer: C Explanation: Placing detectors 30 ft upstream provides sufficient detection time for extension while avoiding early calls. Question 13. The “Extension” logic in an actuated controller means: A) Green ends immediately after the detector clears B) Green is prolonged by a fixed time after the last vehicle is detected C) Green is shortened if no vehicle is present D) Green is replaced by a flashing yellow phase Answer: B Explanation: Extension adds a predetermined time after the detector’s last activation, allowing queued vehicles to clear. Question 14. In the HCM 7th Edition, the “Degree of Saturation” (v/c) for a signalized movement is calculated using: A) Observed volume ÷ saturation flow B) Peak hour volume ÷ (green time × saturation flow) C) Average hourly volume ÷ (cycle length × number of lanes) D) Total intersection volume ÷ total capacity
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C) Vehicles on the minor street and the major street through traffic D) Vehicles entering from opposite directions simultaneously Answer: C Explanation: TWSC relies on the major street’s right-of-way; conflicts arise when minor-street vehicles cross the major street. Question 18. In an All-Way Stop Control (AWSC) intersection, the average vehicle delay is primarily a function of: A) Signal cycle length B) Stop-sign clearance time and queue discharge rate C) Pedestrian crossing time D) Roundabout circulating flow Answer: B Explanation: Without signals, delay is driven by the time needed to clear stopped queues and the clearance interval at each stop sign. Question 19. When modeling a single-lane roundabout, the “Circulating Flow” is defined as: A) The sum of all entering volumes B) The volume that continues around the roundabout without exiting C) The volume that exits at the first off-ramp D) The pedestrian crossing volume Answer: B Explanation: Circulating flow represents vehicles that stay on the roundabout, affecting capacity and conflict calculations. Question 20. The “Cycle Length Partition” tool in Synchro is used to: A) Divide the network into separate timing plans for each hour
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B) Identify the optimal cycle length that minimizes total delay across the network C) Allocate green time equally among all phases D) Generate a pedestrian-only timing plan Answer: B Explanation: The partition algorithm evaluates multiple cycle lengths and selects the one yielding the lowest overall delay. Question 21. In split optimization, a higher volume-to-capacity (v/c) ratio on a movement generally leads to: A) A reduction in its green split B) An increase in its green split C) No change in split allocation D) A shift to a protected-left phase only Answer: B Explanation: To accommodate higher demand, the optimizer allocates more green time to movements with higher v/c ratios. Question 22. An “offset” of 1.5 seconds between two adjacent signals means: A) The second signal starts its green 1.5 seconds after the first signal’s green begins B) The second signal’s cycle length is 1.5 seconds longer C) Both signals have a 1.5-second all-red interval D) The second signal’s yellow interval is 1.5 seconds longer Answer: A Explanation: Offset defines the time difference between the start of the green phases of adjacent signals, facilitating progression.
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Explanation: Lead-lag separates conflicting movements by giving one a brief green before the other, reducing overlap. Question 26. When coding a median-separated link, the correct way to represent it in Synchro is to: A) Create two separate links with opposite directions B) Use a single link with a median attribute flag C) Model it as a roundabout node D) Enter it as a pedestrian path only Answer: A Explanation: Median-separated facilities are modeled as two one-way links, each representing one direction of travel. Question 27. Which parameter controls the “gap-out” logic in an actuated detector? A) Minimum green time B) Extension time C) Gap-out time D) Yellow clearance interval Answer: C Explanation: Gap-out time defines the maximum time after the last detection before the controller terminates the green. Question 28. The “All-Red Clearance” interval is required to: A) Allow pedestrians to finish crossing safely B) Prevent vehicle collisions during phase change C) Reset detector counts D) Provide time for public transit priority
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Answer: B Explanation: All-red ensures that the intersection is clear of vehicles before the next green begins, reducing conflict risk. Question 29. In Synchro, the “Turn Pocket Length” for a right-turn lane is typically set to: A) 5 m B) 10 m C) 15 m D) 20 m Answer: C Explanation: A 15 m pocket provides sufficient space for vehicles to decelerate and complete a right turn without blocking through lanes. Question 30. When assigning a “Signalized” node type, which additional attribute must be defined? A) Pedestrian crossing width B) Controller ID and timing plan C) Median type D) Roadway surface condition Answer: B Explanation: Signalized nodes require a controller reference to link the node with a specific timing plan. Question 31. The “Through-Movement” volume on a link is calculated by: A) Adding all turning movement volumes entering the link B) Subtracting turning volumes from the total approach volume C) Using only the straight-through detector count
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C) It uses video detection only D) It cannot be synchronized with adjacent signals Answer: A Explanation: Semi-actuated systems have detectors on minor approaches, while major movements have fixed times. Question 35. The “Green Split” for a phase is defined as: A) Green time divided by cycle length, expressed as a percentage B) Green time minus yellow time C) Total cycle length divided by number of phases D) Green time multiplied by saturation flow Answer: A Explanation: Split = (Green time / Cycle length) × 100 %, indicating the proportion of the cycle allocated to that phase. Question 36. When calibrating a model, a systematic underestimation of delay suggests you should: A) Increase saturation flow rates B) Decrease the PHF value C) Reduce the minimum green intervals D) Increase the cycle length Answer: D Explanation: Longer cycles generally increase delay; if the model underestimates delay, the calibrated cycle may be too short, so increasing it aligns predictions with observed data. Question 37. The “Critical Lane” concept in a multi-lane approach is used to:
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A) Identify the lane with the highest turning proportion B) Determine which lane controls the movement’s capacity C) Assign pedestrian crossing to the outermost lane D) Set the detector location for the lane furthest from the stop line Answer: B Explanation: The critical lane is the lane that limits capacity (usually the leftmost turning lane) and is used in capacity calculations. Question 38. Which of the following best describes “Band-width Utilization” in progression analysis? A) Ratio of green time to total cycle length B) Percentage of the corridor length that experiences uninterrupted travel C) Number of detectors per mile of roadway D) Average vehicle speed during the green wave Answer: B Explanation: Band-width utilization measures how much of the available bandwidth (distance) is effectively used by traffic progression. Question 39. In Synchro, the “Link Length” attribute is crucial for: A) Calculating travel time between nodes B) Determining the number of lanes required C) Setting the detector sensitivity D) Assigning pedestrian crossing times Answer: A Explanation: Link length, combined with speed, yields travel time, which influences progression and offset calculations.
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Question 43. In a roundabout capacity analysis, the “Entry Flow” is compared against: A) The circulating flow of the roundabout B) The pedestrian crossing demand C) The through-movement volume of the adjacent intersection D) The total vehicle fleet size in the network Answer: A Explanation: Capacity is limited by the ability of circulating traffic to accommodate entering vehicles; entry flow must be less than the available circulating capacity. Question 44. The “Lead Time” parameter in Synchro’s detector settings determines: A) How early a detector must sense a vehicle before green is requested B) The time between green and yellow C) The duration of the pedestrian walk interval D) The length of the detector’s physical coil Answer: A Explanation: Lead time is the detection interval needed for the controller to react and extend green before the vehicle reaches the stop line. Question 45. When performing a “What-If” analysis for a new development, the most appropriate method to estimate additional trips is: A) Using the existing traffic counts unchanged B) Applying a trip generation rate from the ITE manual C) Doubling all existing volumes D) Ignoring pedestrian trips
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Answer: B Explanation: The ITE Trip Generation Manual provides empirically based rates for various land-use types, suitable for estimating new trips. Question 46. The “Cycle Length” that minimizes delay for a signalized intersection can be approximated by the Webster formula: A) C = 1.5 L + 5 (V/S) B) C = 1.5 L + 5 (1 – v/c) C) C = 1.5 L + 5 (V/C) D) C = 1.5 L + 5 (v/c) Answer: D Explanation: Webster’s empirical formula: C = 1.5 L + 5 (v/c), where L is total lost time and v/c is the critical flow ratio. Question 47. In Synchro, the “Lost Time” for a phase includes: A) Yellow change interval only B) All-red clearance only C) Both yellow and all-red intervals D) Pedestrian walk time Answer: C Explanation: Lost time is the sum of yellow and all-red intervals, representing time when no effective green is provided. Question 48. The “Progression Ratio” used in offset optimization is defined as: A) Green time ÷ cycle length B) Offset ÷ cycle length C) Travel time between two signals ÷ cycle length
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B) The number of phases a detector can control C) The color of the detector on the map view D) The pedestrian crossing speed Answer: A Explanation: Detector coverage specifies how far upstream the detector senses vehicles, affecting the timing of extensions and gap-outs. Question 52. The “Maximum Green” limit in an actuated controller is used to: A) Prevent a phase from monopolizing the cycle when demand is high B) Ensure a minimum pedestrian crossing time C) Set the maximum yellow interval D) Define the all-red clearance time Answer: A Explanation: Maximum green caps the duration a phase can stay green, avoiding excessive green time for one movement at the expense of others. Question 53. For a two-lane arterial with a 60 km/h speed limit, the recommended “Band-width” speed used in Synchro progression analysis is: A) 30 km/h B) 45 km/h C) 55 km/h D) 60 km/h Answer: C Explanation: Band-width speed is typically set slightly below the posted speed to account for real-world conditions; 55 km/h is common for a 60 km/h road.
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Question 54. The “Cumulative Delay” output from Synchro is expressed in: A) Vehicle-hours per hour (vph) B) Seconds per vehicle C) Minutes per hour of operation D) Vehicle-seconds per hour Answer: D Explanation: Cumulative delay is the total delay accumulated by all vehicles, measured in vehicle-seconds per hour. Question 55. When assigning a “Signal Coordination” plan across a corridor, the primary objective of offset adjustment is to: A) Minimize the number of phases at each intersection B) Maximize the green wave for the predominant traffic direction C) Reduce pedestrian crossing times D) Equalize saturation flow rates on all approaches Answer: B Explanation: Offsets are tuned so that vehicles traveling at the design speed encounter successive greens, creating a green wave. Question 56. In the HCM, the “Base Saturation Flow” for a protected left-turn lane is typically: A) 1900 veh/hr/ln B) 1800 veh/hr/ln C) 1600 veh/hr/ln D) 1500 veh/hr/ln Answer: D
