GATE Questions & Answers of Control devices, Signal design by Webster’s method

What is the Weightage of Control devices, Signal design by Webster’s method in GATE Exam?

Total 2 Questions have been asked from Control devices, Signal design by Webster’s method topic of Traffic Engineering subject in previous GATE papers. Average marks 2.00.

The queue length (in number of vehicles) versus time (in seconds) plot for an approach to a signalized intersection with the cycle length of 96 seconds is shown in the figure (not drawn to scale).

At time $ t=0 $, the light has just turned red. The effective green time is 36 seconds, during which vehicels discharge at the saturations flow rate, $ s $ (in vph). Vehicles arrive at a uniform rate, $ v $ (in vph), throghout the cycle. Which one of the following statement is TRUE?

The critical flow ratios for a three-phase signal are found to be 0.30, 0.25, and 0.25. The total time lost in the cycle is 10 s. Pedestrian crossings at this junction are not significant. The respective Green times (expressed in seconds and rounded off to the nearest integer) for the three phases are