In traffic signal coordination, what is the ideal cycle length based on travel time of 27 seconds between intersections?

In traffic signal coordination, the ideal cycle length is generally designed to accommodate the travel time between intersections so that vehicles can move efficiently and in a coordinated manner. Given a travel time of 27 seconds between intersections, the cycle length should be a multiple of the travel time to allow for synchronized signal changes.

The correct answer, which is 110 seconds, is derived from the need to consider not just the travel time, but also a buffer or additional time required for the operation of the signals. A cycle length that is slightly longer than the travel time allows for proper signal phases, including green, yellow, and all-red clearance times, as well as any additional delays that may occur due to acceleration and deceleration of vehicles.

Choosing a cycle length of 110 seconds ensures that there is enough time for vehicles to clear the intersection before the signal changes again. This consideration helps minimize delays and improve the overall flow of traffic between the coordinated traffic signals.

In contrast, a cycle length of 27 seconds would not accommodate the necessary signal operation requirements, nor would longer cycle lengths like 54 or 108 seconds provide the additional time needed for smooth traffic flow and compliance with signal timing. Thus, a cycle length of 110 seconds is optimal for effective traffic