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HOW DOES SPEED GUNS WORK?
Hello everyone, I am very happy to see you again in my latest video clip today, in today's video clip, I would like to share with you about the principle of structure. traffic police speed gun operation, and answer some questions such as traffic police speed gun can work when it's raining, when it's dusty, when it's foggy or not? We invite you to watch the video clip!
The first is what is the traffic police speed gun? This is a gun that shoots without death that everyone is afraid of, this gun is what I call it in a slang way, but in fact it is a device to measure the speed of vehicles that are moving, the gun that shoots This speed it has two main categories you guys! The first type is using waves ... electromagnetic waves, the second type is using light, using infrared rays. Then the first type of wave, how does it measure? On the speedometer of the traffic police, it is one that has a broadcast, the other is a receiver. The transmitter will emit electromagnetic waves and it will travel through the air at the speed of light, this electromagnetic wave reaches the car, the car that is shot will bounce back to the machine. collect.
Since this car is not stationary, it is moving, so in the transmitted wave and the reflected wave it will have a frequency change based on the Doppler effect in physics, and it can be measured. How much frequency change will one calculate how fast this car is moving, what is the Doppler effect? The doppler effect is a physical effect discovered by the Italian scientist Christian Andreas Doppler, which states that the frequency and wavelength of sound waves, electromagnetic waves and other types of waves will generally change. When the source of it is moving relative to the observer, for example an ambulance siren coming closer to us, we will hear a more harsh sound, because the frequency of its sound is higher, conversely when this ambulance is moving away from us, then we will hear its sound lower, because the wave it will have a lower frequency.
Now I relate to the water wave so that I can explain it more easily to you, now imagine that on the surface of the water there is a Bug that is making vibrations it vibrates to create oscillations on the surface. water, water waves, these water waves will move and spread to all sides, suppose there are two observers, one at A and one at B, the distance from A to the Bug and the distance from B to the observed Bug, then it oscillates like that it will create a wave with a frequency, I take for example 2 hertz, what does that mean? That is, in a second it oscillates twice, at point A and point B observing this bug's frequency is also 2 herc, because the distance from A, B to the Bug is the same.
Now imagine if the Bug is not still but it moves to the right with some speed i.e. moving towards that B, then the observer at B and the observer at A write receive the frequency wave level does it change or not? Because when the Bug moves to the right of point B, the distance between the Bug to B it will decrease, then the waves that Bug makes it will reach B faster, so which at B the observer will pick up the continuous wave more quickly, which means that person B will perceive the frequency of this wave faster than it actually is at the Bug, and vice versa. At A, because the beetle moves away from A, at point A a wave with a slower frequency will be observed, because the wave it takes longer to arrive. Although the frequency of the Bug's wave is unchanged, what is the advantage of a speed gun that uses this electromagnetic wave?
The first advantage is that it does not depend on the weather, does not depend on the light, it can shoot during the day, at night, in the rain, in the sun... that's… those are the advantages of the speed gun. Using electromagnetic waves, the disadvantage is that it has to be stationary and not moving to measure because when the traffic policeman is sitting on the car traveling in the same direction or in the opposite direction, the speed of the car is shot. it will change, next is the type of speed gun that uses light, this gun it will emit, it also has two parts guys, the first part is emitting light, the second part is to capture light, then you know that light travels through the air at a speed of 300 thousand kilometers per second, which means 300 million meters per second, which is like an electric wave. From now on, the gun it will emit infrared rays, the infrared rays that go to the vehicle being shot, it will bounce back and then bounce back to the receiver, then the receiver will measure the time from the time of destruction. t to the time when the light is received and I know the speed of light in the air and then multiply that speed by the time between the time of emission and return, calculate the distance from the car to that tachometer is to measure the distance.
Continuing in a very short interval of a few hundredths of a second, the speed gun it continues to emit a second infrared ray, this second infrared ray reaches the echoing car, then Because this vehicle is moving, moving forward, so at this second shot, the distance measured will be shorter than the first distance. If we take the distance measured at the first time as D1 minus the distance measured on the second time as D2, then it will be the distance that the car traveled between the two shots, between the two shots. two shots, the gun's speed is already programmed, so it knows how much between two shots? For example, like 1/200 of a second, then fortunately I already have the time interval between two shots and the distance the car travels between two shots, if I take D1 minus D2 the absolute value divided by where T is the time between two shots that will give the vehicle's speed.
The speed number when I pull the trigger like that, it will emit light and return, emit light and return continuously like that, it measures the distance of the car in such a continuous period of time, a contraction is able to measure hundreds of times and then it will measure the speed of the car, hundreds of times then it will add up the average and it will give a number it shows on the screen and that is the result of the speed of my car, measured in infrared, then the infrared it is a more modern type than a radar, because it is a more modern type than using electromagnetic waves, because of the electromagnetic wave gun, it is on some drivers who have a part to detect the waves of the speed gun, then when running on the road with the speed police, use it electromagnetic wave, the machine will receive that wave and make a beep, notify the driver to reduce speed, can receive kilometers as advertised.
If that machine detects the correct frequency of the traffic police speedometer, and this type of light, the machine will tell the hand, because it uses light that cannot use electromagnetic waves, for so that machine can't detect where the traffic police are standing and shooting speed.... That… then this light speed gun has the advantage of being difficult to detect by the driver, it has the disadvantage that it requires shooting when the sky is clear, no dust, no fog and there's no rain, there's no obstacle between the gun and the car, if obstructed, the light will be different and it won't be accurate, that's… those are two types of speed guns. I have shown you and how to avoid speed shots, I advise you to go at the correct speed on that stretch of road, the allowed speed, the allowed limit I posted two videos the other day. Recently talked about speed in residential areas, outside residential areas, double roads, one way roads, two way roads for cars, motorbikes and trucks etc.
And you should note that where there is a speed limit sign, that is the white background sign with red border ... 50km/h, 60km/h, please obey that sign, otherwise you will be traffic police blow back and be punished very heavily, currently violating the speed of punishment is very heavy, today's video clip I have just presented to you about the operating principle of the traffic police speed gun. information, thank you very much for watching my video clip, if you have a topic about cars that need me to make a video clip, please comment below, I will research and find research materials, If I can research, I will make the video clips that you have requested, not all of the topics I can do, but I will try my best to make video clips for you.
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