Question

what is the state of traffic signal (a) with respect to surroundings​

Answer 1

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Traffic lights, traffic signals, stoplights or robots are signalling devices positioned at road intersections, pedestrian crossings, and other locations to control flows of traffic

Answer 2

Answer:

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Explanation:

Adaptive Traffic Control System (ATCS) is a solution that automatically adapts the timings of traffic lights based on real-time traffic conditions to optimize the flow of traffic.

The world's first traffic light was a manually operated gas-lit signal installed in London in December 1868. It exploded less than a month after it was implemented, injuring its policeman operator.[3] Earnest Sirrine from Chicago patented the first automated traffic control system in 1910. It used the words "STOP" and "PROCEED", although neither word was illuminated.[4]

Traffic lights follow a universal colour code which alternates the right of way accorded to users with a sequence of illuminating lamps or LEDs of three standard colours:

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