Today, everyone understands what a traffic light is. Colors: red, yellow and green - are familiar even to a child.
However, there was a time when these optical devices were not there, and crossing the street was not very easy. Especially in large cities, passers-by had to skip endless horse-drawn carts for a long time.
On the cross streets there was confusion and endless debate.
A small digression into history
Initially, the British came up with a traffic light. It was delivered in London at the end of the year 68 of the 19th century. Man controlled it. The mechanism had two arrows. When they were in a horizontal position, movement was forbidden, and when lowered, travel was allowed. At night, a gas burner was turned on, with which a red and green signal was emitted. This turned out to be unsafe. The gas exploded, injured the policeman, the traffic light was removed.
Only at the beginning of the twentieth century in America was an automatic traffic light patented. Colors were not used in it, replaced their inscriptions.
But the first traffic light, which is similar to the modern one, was developed in 1914 in the same America. The first luminous traffic light was installed in Cleveland, there were only two colors: red and green. And in 1920, a third was added to these two colors - yellow.
In the Soviet Union, the first traffic light was installed in Leningrad in 1930, and a little later in Moscow, however, the arrangement of flowers was the opposite. Above was green, and below - red. Only in 1959 in our country traffic lights began to look like all over the world. So they look to this day.
Today, in any city, traffic lights are a common occurrence, without which traffic is not possible.
The principles of operation of modern traffic lights
The traffic light is designed to regulate the movement of vehicles and is a lighting device installed in a certain place with the sequential switching of light signals of certain colors.
A specially designed automated program controls the traffic light. In cities, these programs are global. They are carefully designed. Such programs are controlled by several traffic lights at once, and to optimize the movement of software is developed for each time of day separately.
Where do they usually set traffic lights
In all densely populated cities, traffic control is currently a traffic light. The colors are switched in order and thereby regulate the movement.
They must be installed at crossroads of equivalent roads, at pedestrian crossings with a large crowd of people, near educational institutions and in other places where additional regulation is necessary.
In large cities, traffic lights are installed on almost any highway at bus and tram stops, near metro stations.
Traffic light red
Everyone knows that red is an aggressive, exciting, screaming color. It means danger. At traffic lights, red is prohibitive. Even in kindergarten, children are taught: "Red - no movement."
For road users, a red traffic signal indicates that traffic outside the stop line is prohibited. All cars without exception must adhere to this rule. For crossing an intersection with a prohibitory traffic signal, traffic rules provide for penalties. These fines are quite large and well-deserved, because driving to the red color can be very dangerous. It is because of irresponsible drivers at traffic lights and intersections that the most terrible accidents sometimes occur .
The red color is very clearly visible in any weather: when the sun is shining brightly, it is raining, or there is fog. From a physical point of view, red has a maximum wavelength. Perhaps that is why he was chosen as a forbidden one. Throughout the world, the meaning of red is the same.
Traffic light green
Another signal at the traffic light is green. It is the color of calm, peace. It has a relaxing effect on the human brain. A green traffic light allows traffic. You can see it far enough, any driver, long before the traffic light passes, sees this color and calmly, without braking, overcomes the intersection.
However, as they say, there is an unwritten rule according to which it is still worth braking when driving through a dangerous intersection, even when the traffic light shows green. This action often helps to avoid serious accidents.
Yellow - pay attention
The yellow color of the traffic light is intermediate. It carries a warning function and encourages participants to pay attention. They say that yellow color symbolizes the mind, intuition and quick wit. It usually lights up after red, urging drivers to prepare for the movement. As practice shows, many drivers perceive the yellow traffic light as allowing and begin to move. This is wrong, although not punishable by penalties. When the yellow color lights up, you need to squeeze the clutch, get ready, but to start the movement it is better to wait for the green, especially since only a couple of seconds to wait.
In the reverse order: green, yellow, red - the traffic light does not work. In modern devices, after the green, the red color immediately lights up, while in the last minutes the green starts to blink.
Also sometimes you can see a continuously flashing yellow traffic signal. This indicates that the traffic light is turned off or broken. Most often, the traffic lights flash yellow at night.
Pedestrian traffic light
There is also a traffic light to control pedestrian traffic. What colors are used in it? Red and green - definitely, but yellow is absent as unnecessary. Special preparation for crossing the road is not required for a person.
Usually depicting walking people at pedestrian traffic lights . For the convenience of pedestrians, a time counter has recently been used. A special stopwatch counts how many seconds are left before the opposite signal is turned on.
As in ordinary traffic lights, red color prohibits movement, and green indicates that the passage is open.
Driving through an intersection, drivers should know that pedestrians take advantage. So, for example, at a crossroads, the car turns right at a green traffic light, while pedestrians crossing a perpendicular road are also green. In this case, the motorist must skip all pedestrians and only then continue driving.
What is a green wave?
In large cities, traffic on highways is accompanied by a large number of traffic lights that regulate traffic. A traffic light, the colors of which are known to everyone, switches them with a certain frequency. This frequency is automatically adjusted and ensures the safety of vehicles.
The “green wave” is tied to the speed of the car. It is assumed that, moving at a certain average speed, the driver, having caught the green traffic light, will also fall into green along the entire length of the highway. Three colors of the traffic light switch at regular intervals, and there is consistency between a number of traffic lights. At all intersections of the highway, agreed on this principle, there is the same cycle.
The “Green Wave” was designed for the convenience of crossing intersections; technically, this is not particularly difficult. As a rule, signs with the recommended speed, which will ensure uninterrupted passage of intersections, are additionally installed on such highways.
Assistant driver and pedestrian is a three-eyed traffic light. The colors switch in order and adjust the course, ensuring the safety of all road users. By observing the intersection rules in good faith, serious accidents and unpleasant situations on the roads can be avoided.