Instruction
Lightning is dangerous to human life. However, ironically, it is through the fault of people that there are more and more of them. This happens due to an extremely irresponsible attitude to the environment: ambient air pollution in megacities increases the heating of the air and the rise of steam condensate into the atmosphere. This amplifies the electrical intensity in the clouds and provokes lightning discharges.
The need to determine the distance to lightning is caused not only by the need to expand one's horizons, but also by the elementary instinct of self-preservation. If it is too close, and you are in an open space, then it is better to run away from there as quickly as possible. The electric current chooses the shortest path to the ground, and the skin is an excellent conductor for it.
Start counting seconds as soon as you see a flash of light in the sky, use a clock or a stopwatch. As soon as the first roll of thunder is heard, stop counting, so you will get time.
To find the distance, you need to multiply the time by the speed. If accuracy is not very important for you, then it can be taken equal to 0.33 km / s, i.e. multiply the number of seconds by 1/3. For example, according to your calculations, the time to lightning was 12 seconds, after dividing by 3 you get 4 km.
To determine the distance to lightning more accurately, take average speed in the air equal to 0.344 km/s. Its true value depends on many factors: humidity, temperature, type of terrain (open space, forest, urban high-rise buildings, water surface), wind speed, etc. For example, when it rains autumn weather the speed of sound is about 0.338 km/s, in dry summer heat it is about 0.35 km/s.
Dense forest and tall buildings significantly slow down the speed of sound. It decreases due to the need to go around numerous obstacles, diffraction. It is quite difficult to make an accurate calculation in this case, and most importantly, it is not advisable: despite the fact that lightning will not strike the ground, it can hit a tall tree next to you. So wait it out between low-growing trees with a dense crown, best of all on your haunches, and if you are on a city street, then take cover in a neighboring building.
Notice the wind. If it is strong enough and blows in your direction away from the lightning, then the sound is coming faster. Then its average speed can be taken approximately equal to 0.36 km/h. When the direction of the wind is from you to the lightning, the movement of sound, on the contrary, slows down and the speed is approximately equal to 0.325 km/h.
The average length of lightning reaches 2.5 km, and the discharge extends over a distance of up to 20 km. Therefore, you should leave the open place as soon as possible in the nearest building or structure. Remember that when lightning approaches, you need to close all windows and doors and turn off electrical appliances, as damage can occur through the antenna and through the network and harm your equipment.
Lightnings are not only terrestrial, but also intra-cloud. They are not dangerous for those who are on the ground, but they can damage flying objects: airplanes, helicopters and others. vehicles. In addition, a metal object caught in a cloud with a strong electric field, capable of supporting, but not creating a charge, can become the initiator of lightning and provoke its appearance.
In nature, weather phenomena often occur, which, under certain conditions, are dangerous to human health. Statistics for the last day emergencies Unfortunately, a thunderstorm filled up.
In the forest near the settlement. Starobin, Soligorsk district, Minsk region, a student born in 1996, who was with a group of children in a tent near a tree, was mortally injured by a lightning bolt (there were 11 children accompanied by 4 adults on vacation). Three more teenagers were hospitalized with electrical injuries of varying severity.
In this connection, the Mogilev city department reminds the townspeople what to do to avoid possible dangerous consequences of this natural phenomenon.
To determine how far a thunderstorm is, approaching or receding, you need to note the time between a flash of lightning and the subsequent roll of thunder. Sound travels about 1 km in 3 seconds. If the time from a flash of lightning to thunder is gradually decreasing, then a thunderstorm is approaching you. Based on this, you can calculate the approximate distance to the epicenter of a thunderstorm and take measures to ensure your safety. The most dangerous situation is when thunder rumbles immediately after the flash of lightning - it means that the thundercloud is already directly above you.
If by all indications it is clear that thunderstorms cannot be avoided, we act depending on the situation.
Rules of conduct during a thunderstorm:
Option 1. You are at home
- if a thunderstorm caught you at home, close windows and vents, move away from the window, avoid drafts that could attract fireballs,
- do not touch water taps and batteries,
- don't use a regular phone- even here you can be overtaken by an electric discharge,
- try to stay away from electrical outlets;
- disconnect from electricity computer, TV and other electrical appliances;
- don't talk on your cell phone;
- it is better not to heat the stove or fireplace at this time, since the smoke coming out of the chimney has a high electrical conductivity, and the likelihood of a lightning strike into the chimney increases.
Option 2. You are in the city
Do your best in the city rather take cover in a shop or apartment building. They have reliable lightning protection, unlike stops public transport. If there are no such options, wait out a thunderstorm by squatting under low plantings.
Mobile phone while on the street immediately disable.
Using a mobile phone outdoors during a thunderstorm poses a serious threat to life and health due to the danger of lightning. There have been numerous cases of people dying from lightning strikes while talking on a mobile phone.
Option 3. You are in the forest
Lightning in a forest almost never strikes the ground, with the exception of clearings, because trees are natural lightning rods, and the probability of lightning hitting a particular tree is directly proportional to its height.
Stay away from tall trees. The smartest option sit between low trees with dense crowns. At the same time, determine the approximate height of the trees you have chosen and try be placed from them at a distance not exceeding this height. Let's say the height of the trees is about 4-5 meters, respectively, it is necessary to place between them so that each of the trees is at least 4-5 meters away. This is called the "cone of protection".
Moreover, it must be remembered that most often lightning strikes oak trees, poplars, elms - as they contain a lot of starch. Less often - in spruce, pine, fir - as they contain a lot of oils, therefore they have great electrical resistance and are less likely to be struck by lightning. Quite rarely - in birches, maples.
Sit better in the so-called fetal position"- the back is bent, the head is lowered on the legs and forearms bent at the knees, the feet are joined together.
When choosing a shelter for yourself, pay attention to whether there are nearby trees that were previously hit by a thunderstorm, split. In this case, it is better to stay away from this place. The abundance of trees struck by lightning indicates that the soil in this area has a high electrical conductivity, and a lightning strike in this area is very likely.
It is also best to pitch tents in a small clearing in the middle forest. Putting up tents in the open is dangerous.
Option 4. You are in the field
At the first sign of an approaching thunderstorm: move to the side reliable nearest shelters(forest, village), moving away at the same time from separate trees or groves. With the onset of a thunderstorm, if you still haven't made it to shelter: sit as close to the ground as possible. It should be remembered that sandy and stone soils are safer than clay soils.
It is forbidden: move quickly, hide in haystacks, under lonely standing trees or islands of trees, especially touch them with hands and other parts of the body. The psychology is such that a person tends to see protection in something big and powerful. In a thunderstorm, the reverse law works: the smaller you are, the more chances you have not to fall under the category. Therefore, we go around the trees.
Option 5. You are in the river, and there is a water meadow nearby
It is forbidden: climb into the water; hide in the floodplain bushes and, again, under the trees. It is necessary as soon as possible (but not running, if the thunderstorm has already begun) to get to the nearest forest (but not individual trees in the open area) or to the village. At the same time, try to avoid, two hundred meters away, lonely trees and other tall objects.
A person on a boat, when a thunderstorm approaches, should immediately land on the shore.
Option 6. The storm caught you in the car
Many people mistakenly believe that it is dangerous to wait out a thunderstorm while sitting in a car. In fact, the machine protects the people inside quite well, since even with a lightning strike, the discharge goes through the surface of the metal. Therefore, if a thunderstorm caught you in the car, close all windows and wait until the bad weather passes.
However not should touch before door handles and other metal parts. Including cell phones. Spare your eardrums - in a thunderstorm, you can get a sonic boom through a mobile phone in your hands.
Option 7. You are on a bike
A bicycle and a scooter, unlike a car, will not save you from a thunderstorm.
If you are caught in a thunderstorm while riding a bicycle or motorcycle, stop moving, leave them and wait out the storm at a distance about 30 meters away.
Option 8. If you are on a hike
During a thunderstorm, all metal objects: axes, saws, shovels, knives, dishes, etc. - must be folded 15-30 m from the camp or people.
From the soil, especially if it is wet, it is necessary to isolate, placing a heat-insulating rug, air mattress, branches, spruce branches, in extreme cases, stones, ropes, clothes, shoes, etc. under you. at the same time, it is necessary to strive so that the insulator is as dry as possible!
You should sit in a group, bending your back, lowering your head on your legs and forearms bent at the knees, connect your feet together. The body should have the least contact with the ground. It is desirable to remove wet clothes and put on dry ones, in extreme cases, carefully squeeze them out. Wet body and clothing increase the risk of being struck by lightning.
When the storm starts, put out the fire. Smoke is a good conductor of electricity. There were, for example, cases when lightning struck a low pipe, although there was a tall one nearby. And all because the "shorty" smoked with might and main.
When sheltering from a thunderstorm, also avoid characteristic faults on the ground. Experts call them "lightning nests" - they are the most conductive areas of the soil.
On the way, the group is better to disperse. Go one at a time, don't rush.
During a thunderstorm, in no case do not run and do not fuss.
You can not be in wet clothes and shoes.
Ball lightning
About a year ago, on the morning of July 12, residents of Yamnitsky 5th Lane witnessed one of mysterious phenomena nature of ball lightning. A large light ball with a diameter of about 2 meters came into contact with a television antenna installed on one of the houses, after which it exploded and, having split in two, disappeared, leaving behind three sources of ignition on the roof at once. At the time of the incident, there was a girl born in 1994 and her 48-year-old father in the house, who was doing housework in the courtyard of the house. Neighbors reported the fire. When rescuers arrived, the house was on fire. As a result of the fire, the roof was destroyed by fire, property in the house was damaged.
Ball lightning can suddenly appear anywhere, even indoors. There were cases of her appearance from a telephone receiver, an electric razor, an outlet. Eyewitnesses claim that ball lightning can enter a room through narrow cracks, pipes, and even a keyhole. The size of ball lightning can be from a few centimeters to several meters. Usually it easily floats or rolls above the ground, sometimes jumps. Ball lightning can appear and disappear without causing harm to a person or a room. And it can leave behind a hole in the door and the smell of ozone. She often explodes. Statistics says that in 80% of cases explosions were not dangerous, serious consequences occurred in 10% of explosions.
What to do if, nevertheless, ball lightning has flown into your house?
When meeting with ball lightning, keep calm and stop the slightest movement.
Shouldn't run away from ball lightning, because you can cause an air stream, through which a clot of energy will fly purposefully after you.
No need to approach her, touch her with anything, as an explosion may occur.
Important!!!
If there is a person next to you, struck or shell-shocked by lightning, do not be afraid to touch him- no charge remains in the victim's body. It must be remembered that not every lightning strike is fatal!
A person can be helped by providing first aid. The main cause of death in a lightning strike is a violation of the activity of the heart and lungs. Therefore, the victim should do artificial respiration and heart massage without stopping for more than a minute, and stop only when the victim has obvious signs of death.
If a thunderstorm takes you by surprise, you need to remember the following:
- lightning never strikes a bush;
- avoid isolated trees;
- put metal objects aside;
- do not stand under an open umbrella;
- do not touch electrical objects and take them out of pockets;
- if possible, wait out the storm in the car;
- stay away from tall metal structures;
- do not swim, do not ford the river, move away from the reservoir.
Once in extreme conditions, act decisively, using all the baggage of your knowledge and skills.
In chapter Science, Technology, Languages to the question How can you measure the distance to a thunderstorm? given by the author Aggressive noob the best answer is the distance to a thunderstorm can be determined by the time between a flash of lightning and a roll of thunder (1s - distance 300-400 m, 2s - 600-800 m, 3s - 1000 m)
Answer from Ekaterina Kurzeneva[guru]
For some reason, my parents explained to me this way: Count the seconds between the flash of lightning and the first clap of thunder. 1s-1 km.
Answer from Vasisualy Levaterenolovich[guru]
It was found that the speed of sound is 171 toise per second, which corresponds to 337 m / s. Therefore, 3 sec ~ kilometer
Answer from Serrrega[guru]
No.. I'm not against physics.. .But.. I want to put in my twenty cents... .Maybe I'm wrong. . But a thunderstorm does not COMING from one point... This is generally a global phenomenon... And counting the seconds between the appearance of lightning and thunder is incorrect, you'll excuse me... I observed thunderstorms when lightning was present for three seconds in the form of a flash within a radius of 180 degrees.. (left-right-front). And the thunder rumbled. then .... peal and stereo ... Your subwoofers and stereo effects are resting ... And how is it???? This is Moscow suburbs... I don't go far... I saw lightning but didn't hear thunder.. I heard thunder.. But I didn't see lightning.. How is that? How is it with D. Granin? "I'm going to the storm" 🙂
Answer from B and x r b[guru]
Hello!
Everything is pretty simple. Turn on the stopwatch at the moment of the lightning flash, and turn it off when the sonic boom begins. Multiply the number of seconds by 340 (cf. the speed in m/s of sound) and get the distance to the lightning in meters! If you make several such observations in a row and write down the results, you can calculate whether a thunderstorm is approaching you or moving away from you, and even at what speed it happens!
But at the same time, you need to keep in mind that lightning can have a length of several kilometers (see photo) and therefore the sound comes to you with a time shift from different parts of the lightning and therefore the thunder begins to "grumble" as the sound approaches from more distant sections of the lightning. At the same time, close lightning gives a higher-frequency sound, and distant lightning gives a low-frequency sound, since at large distances the high frequencies of the sound "extinguish", and long-wave low-frequency ones penetrate long distances, which is why only low-frequency "grunts" come from distant lightning.
I am enclosing a photo of the lightning, which, according to the calculations of its parameters, showed that the thickness of the lightning rod was about 50 m!
All the best.
Summer Thunderstorm, Arizona (2008)
What are the chances that YOU will be struck by lightning?
The US National Weather Service has calculated that there is a 1 in 300 chance that one of your family members will be struck by lightning at least once.
The temperature of lightning varies from 30,000 degrees Fahrenheit (approximately 16,649 degrees Celsius) to 50,000 degrees Fahrenheit (27,760 Celsius). This is even more than the surface temperature of the sun! When lightning strikes, the air near it is heated to the same temperature and immediately explodes, sending vibrations or sound waves that are reflected from hills, buildings, trees. You can hear thunder from lightning that strikes 32 km away, depending on wind direction and temperature.
"Rule 30 to 30":
If the time interval between the flash of lightning and the roll of thunder is less than 30 seconds, then you are in a zone of dangerous proximity to it.
FACT: If a thunderstorm catches you outside and you are far from cars and buildings, try to find shelter from dense wood or look for plantings of low trees. If you are somewhere where there is nothing like that, for example, in an alpine area, then try to bend down and sit as low as possible, at the bottom of a ravine or gullet, take the fetal position and do not get up. The legs should be together, the head bent to the chest, cover the ears with your hands.
FACT: If you "stretch" on the ground, you will be lower than if you were squatting, but this position increases the chances of an earth shock.
After the end of the thunderstorm, wait 30 minutes (since the last flash of lightning or thunder) before leaving. But be careful!
Even the "30 to 30 rule" will not save you from the first lightning flash, so always be aware of the weather forecast and possible thunderstorms.
Lightning Facts:
The human body does not "store" current. So you can absolutely safely touch a victim struck by lightning and provide first aid.
The lightning diameter is usually about 1.2-2.5 cm, but in some cases it can reach 13 cm. The average lightning length from clouds to the ground is about 5-6 km.
According to observations, about 2000 thunderstorms can occur simultaneously around the world.
Distance from lightning to thunder can be found by multiplying the number of seconds (from the moment we saw to the moment we heard) by the speed of sound equal to 331 m/s. For example, 5 seconds multiplied by 330 (round up) = 1650 meters.
Usually we see a flash of lightning flickering, this is because several lightning strikes almost simultaneously.
The longest (to date) lightning was recorded in Dallas Fort Worth, Texas. She reached 190 km.
Lightning strikes 30 million points on earth per year in the US.
Lightning can appear not only in a thunderstorm, but also during a snowstorm, a sandstorm, over an erupting volcano, or from a nuclear explosion.
The largest fire in terms of the number of victims (12 people), which was caused by lightning, occurred in January 2006 in West Virginia, as a result of a coal mine explosion. The explosion occurred about three kilometers from the entrance to the mine, methane ignited due to lightning, which struck near the mine and entered it through an iron wire.
If lightning is about to strike somewhere near you, then the following usually happens before this:
- Hair is electrified
- tingling skin
- You can hear a sound like something is cracking
- Keys or other metal objects may vibrate
Thunderstorm over the Bering Sea
Where are the most victims struck by lightning?
US state statistics:
- Florida
- Michigan
- North Carolina
- New York
- Wyoming
- Pennsylvania
- New Mexico
- Arkansas
- Colorado
- Georgia
The northern states lead the list. Perhaps the reason for this is that these statistics included victims who simply did not take the necessary precautions.
Thunderstorm over Lake Alcheras, Idaho, USA
Case at Fort Benning (1989): Several thousand people are admitted to hospitals in the United States every year, their injuries are associated with lightning strikes. About 600 of them die. In most cases, lightning strikes one person, rarely when it hits a group of people. There was a massive strike at Fort Benning where 10 soldiers were struck by lightning during an exercise. All the victims survived, none of them lost consciousness, but two soldiers showed memory gaps. All were hospitalized and examined for possible complications. 90% suffered first-degree burns, and all complained of poor eyesight. On the high blood pressure 40% complained, tinnitus — 20%. All ten recovered and returned to active life.
Trees and lightning
Trees quite often conduct lightning into the ground. Tree sap is a poor conductor, therefore, due to electrical resistance, it heats up to such a state that it turns into steam, and under pressure "blows" the bark out of the path of lightning. Over time, bark grows on the damaged areas of the tree, and the tree is almost completely restored, leaving only a vertical scar on it. But if the damage is too severe, then the tree may not recover. Then it dies of decay. It is believed that lightning strikes a single tree much more often, but despite this, in some forests you can find vertical scars on almost every tree.
tall pine
Oak and elm are the two trees that lightning strikes most often, pine being the third most frequent. Pine, unlike oak, has a deep root system, going into groundwater. Pine trees are usually much taller than other trees, which increases the chances of being struck by lightning. It also contributes to lightning strikes high content resins and needles, which are just perfect for electric ignition during a thunderstorm.
The principle of "behavior" of lightning:
Despite the fact that lightning discharges appear most often under clouds, it can still strike the ground anywhere if there is a thundercloud near it. How this process happens:
Lightning strike occurs in ½ second. There are two key concepts associated with the lightning strike process. This is a shifting leader and a reverse discharge. Using them, you can track the process from the moment the lightning leaves the cloud to the connection with the Earth. The shifting leader is a weak lightning bolt inside the cloud. Such discharges move towards the ground in "serial steps", each step down is approximately 45 meters in length. When the shifting leader descends and connects to the ground or a tree (for example), the circuit is completed and lightning strikes. A reverse discharge is a lightning discharge that originates from the earth. He returns to the cloud. There is another concept - a leader. The leader appears when the electrons are discharged. It descends along the initial lightning path to the ground itself. This makes it possible for lightning to strike the same place several times. Lightning has "favorite" places to strike and it can follow the same path twice, despite the beliefs of some.
Thunderclouds over Denver
[Recent statistics have shown that in the state of Arizona, 10 to 20 people are struck by lightning every year, and one of them is bound to die.]
Everyone can determine the distance to a thunderstorm (thunderstorm).
We at school with students determined this distance by calculating the path traveled by thunder peals (sound) to the observer. And every time this calculation turned out to be correct in the required approximation. To do this, we recorded the time at the moment of the lightning discharge and counted until the appearance of thunder. Usually it is from 2 to 15 seconds. More distant thunderstorms could not be detected.
So, here is an example of calculation, if 8 seconds have passed from lightning to thunder, then the thunderstorm is at a distance of 8 x 330 m / s (speed of sound in the air) = 2640 meters. Then we calculated when the storm would reach us. If the wind speed is 20 m/s, then the thunderstorm should reach the place of observation in 2640: 20 = 132 s, or in more than 2 minutes. During this time, you will be able to take precautionary measures (switch off electrical appliances, close windows, etc.)
A simple way to determine the distance to a thunderstorm requires only a watch with a stopwatch.
★★★★★★★★★★
It is possible to determine the distance to a thunderstorm, and it is quite simple to do this if you have a watch with a stopwatch. And even if you don't have them.
Seeing a flash of lightning, you must immediately detect the seconds on the clock before the thunder roll: one second equals approximately 200-300 meters, two seconds - 400-600, three seconds - 600-800, etc. If there is no clock, then you can count: one-two-three, and in order to more accurately determine the seconds, it is better to count: eleven-twelve-thirteen. By the time you say the word eleven, just one second has passed.
Even in such extreme situation we can recommend the following rules of conduct: you can not stand on a hill in a thunderstorm; you can’t move in a dense group, it’s better to scatter in different directions; should not be near metal objects; you can’t hide under a large, lonely tree; if you are near a car, it is better to get into it, since rubber tires do not conduct electricity and this will help you avoid sad consequences.
In a thunderstorm, you must be very careful and do not forget the precautions. At first glance it seems that there is nothing dangerous in this natural phenomenon no. But after all, so many accidents happen in a thunderstorm! When lightning cripples human destinies! Take care of yourself and your loved ones!
Therefore, for security purposes, one should take into account the fact that lightning, most often, goes along with thunder. If you hear that it is thundering closer and stronger, it means that lightning may flash nearby (although it can be seen from afar).
So go to a safe place at this time.
A flash of lightning - we count aloud "one, two, three ...", not very fast and not very slow, as we would simply pronounce these words. At what number did you hear the thunder - so many kilometers to the place of the lightning strike.
Where it comes from, I don't remember. Maybe my grandmother taught me. I checked a couple of times when it was possible to find out exactly where the thunderstorm was. The results are more or less the same.
