Normal atmospheric pressure in mmHg. What atmospheric pressure can be considered normal for humans?
Goals and objectives: to continue the formation of knowledge and ideas about the atmosphere; discuss new concepts and definitions with students; consider the types, magnitude, reasons for changes and methods of measuring At. D.; prove to students the existence of At. D.; show integration with biology - barometer plants; develop the ability to generalize, highlight the main thing, draw analogies, identify cause-and-effect relationships; to introduce geographical terms, to form a conscious discipline.
Lesson format:
conversation, demonstration of experience proving the existence of At. D (sheet of paper and glass of water). Solving practical problems in At. D.Lesson type:
explanation of new material.Equipment:
aneroid barometer, glass of water, sheet of paper, textbook, atlas for 6th grade.Terms and concepts:
At. D., normal pressure, mercury barometer, aneroid barometer. Evangelist Torricelli is explanatory, illustrative, reproductive, problematic.DURING THE CLASSES
1. Organizational moment.
2. New topic after practical work.
Every substance has its own weight and mass, and even air. Air exerts pressure on all objects it comes into contact with, for example, an experiment with a glass of water and a sheet of paper.
The mass of 1 m 3 of air above sea level is 1 kg 300 g
If we take a column of air from the earth's surface to the upper boundary of the atmosphere, it turns out that on 1 cm 2 of the surface, the air presses with the same force as a weight weighing 1 kg 33 g (1 m 2 = 10,000 cm 2 x 1.33 = 13 300 kg (13 t 300 kg)
Let's try to calculate the pressure exerted by the atmosphere on your palm.
Palm area is 60 cm 2 x 1.33 kg = 79.8 kg
Guys, why don’t we or other living organisms feel the pressure that puts pressure on us? (Because it is balanced by the internal pressure that exists inside the human body). Here we come to the definition - Atmospheric pressure is the force with which air presses on the earth's surface and all objects located on it ( write it down in your notebook).
Who measured and established what atmospheric pressure is?
In the 17th century The Italian scientist E. Torricelli proved that atmospheric pressure exists.
He conducted the following experiment: He took a tube 1 m high, sealed it at one end and poured in mercury (this is a liquid poisonous metal Hg), turned the tube over into a bowl of mercury and opened it, part of the mercury poured out, and some remained in the tube. If Atm. D. weakens, then the mercury will pour out a little more; if it increases, the column of mercury will rise.
What prevented the mercury from pouring out completely? (Air pressure puts pressure on the mercury in the cup and prevents the mercury from spilling out) as the experiment with a glass of water showed.
Now let's turn to the textbook, page 144
It has been established that normal Atm. D. is 760 mmHg. at sea level at parallel 45° (Fig. 72) write it down in your notebook.
How is Atm measured? D.?
Barometer (mercury) from the Greek baros - weight, metreo - measure. It is used at all meteorological stations, where in addition a barograph is also installed.
An aneroid (without liquid) is a box from which air has been pumped out. If the pressure increases, the box contracts; if it decreases, the box expands; the arrow shows the change in its volume.
If Atm. D. goes down - then it’s to (to rain)
If it rises, then it’s to 
(to clear weather)
But how does atmospheric pressure change?
Let's look at Fig. again. 72
Conclusion: it means pressure will decrease with altitude. And after how many meters?
With altitude, the air becomes less dense, the oxygen in it decreases, and it becomes more difficult to breathe. Therefore, when a person climbs the mountains already at an altitude of 300 m, he begins to feel bad - shortness of breath, dizziness, and nosebleeds appear.
Every 10.5 m Atm. D. decreases by 1 mm Hg. Art.
Atmospheric pressure also varies with temperature. Warm air is lighter (expands) - Atm.D. – low; cold air is heavier (compressed) Atm. D. – high.
In nature, there are plants that can sense changes in Atm.D. and predict the weather (clover, violet, adonis, field bindweed, white water lily - “Entertaining biology” p. 83; take flower reproductions from your biology teacher).
Where can you use the material you are currently studying in class? (Students' answers).
3. Consolidation
Question No. 2.
a) cold weather – Atm increases. D.
b) warm weather - Atm decreases. D.
Question No. 5. The height of Kazan according to the atlas is 200 m; latitude 54.5° N Do you need to find out what pressure is in Kazan? 200 m / 10.5 m = 19.04 mm; 760 mm – 19.04 =741 mm Hg.
Problem: At the foot of a mountain at an altitude of 2300 m above sea level, the air pressure is 756 mm, and at the top of the mountain at the same time it is 720 mm. Determine the relative and absolute height of the mountain?
756 mm – 720 mm = 36 mm x 10.5 m = 478 m (relative height)
478 m + 200 m = 678 m (absolute height)
Figure No. 1
Problem: If the pressure at the foot of the mountain is 760 mm, then what will the pressure be at an altitude of 336 m?
336 m / 10.5 m = 32 mm;
760 mm – 32 mm = 728 mm Hg.
4. Homework: § 38 question No. 3; No. 4
Atmospheric pressure is the force with which a column of air presses on a certain unit area of the Earth. It is often measured in kilograms per square meter, and from there it is converted to other units. Atmospheric pressure varies around the globe, depending on geographical location. Normal habitual blood pressure is extremely important to the human body for full functioning. You need to understand what atmospheric pressure is normal for a person, and how its changes can affect well-being.
When you rise to a height, the atmospheric pressure decreases, and when you go down, it increases. Also, this indicator may depend on the time of year and humidity in a particular area. In everyday life it is measured using a barometer. It is customary to indicate atmospheric pressure in millimeters of mercury.
The ideal atmospheric pressure is considered to be 760 mmHg, but in Russia and most of the planet in general, this figure is far from this ideal.
The normal force of air pressure is considered to be that at which a person feels comfortable. Moreover, for people from different habitats, the conditions at which normal well-being is maintained will be different. A person usually gets used to the indicators of the area in which he lives. If a resident of the highlands moves to the lowlands, he will experience discomfort for some time and gradually get used to the new conditions.
However, even at a permanent place of residence, atmospheric pressure can change. This usually happens with changing seasons and sudden changes in weather. In this case, people with a number of pathologies and congenital weather dependence may experience discomfort, and old diseases may begin to worsen.
It is worth knowing how you can improve your condition if there is a sharp drop or increase in atmospheric pressure. You don’t have to immediately run to the doctor - there are home techniques that have been tested by many people that can help you start feeling better.
Important! It is worth noting that people sensitive to changing weather conditions should be more careful when choosing places to spend their holidays or move.
What indicator is considered normal for a person?
Many experts say: normal pressure for a person the figure will be 750–765 mmHg. It is easiest to adapt to indicators within these limits. For most people living on plains, small hills, and lowlands, they will be suitable.
It is worth noting that the most dangerous thing is not increased or decreased indicators, but their sudden change. If changes happen gradually, most people won't notice them. A sudden change can lead to negative consequences: Some people may faint during a sharp climb uphill.
Pressure norm table
In different cities of the country, the indicators will be different - this is the norm. Usually detailed weather reports tell you whether the atmospheric pressure is above or below normal. this moment time. You can always calculate the norm for your place of residence yourself, but it is easier to refer to ready-made tables. For example, here are the indicators for several cities in Russia:
| City name | Normal atmospheric pressure (in millimeters of mercury) |
| Moscow | 747–748 |
| Rostov on Don | 740–741 |
| Saint Petersburg | 753–755, in some places – up to 760 |
| Samara | 752–753 |
| Ekaterinburg | 735–741 |
| Permian | 744–745 |
| Tyumen | 770–771 |
| Chelyabinsk | 737–744 |
| Izhevsk | 746–747 |
| Yaroslavl | 750–752 |
It is worth noting that for some cities and regions large pressure drops are normal. Local residents are usually well adapted to them; only a visitor will feel unwell.
Important! If weather dependence occurs suddenly and has never been observed before, you should consult a doctor - this may indicate heart disease.
Effect on the body
For people with certain medical conditions and increased sensitivity to weather changes, pressure changes can negatively affect them, in some cases limiting their ability to work. Experts note: women are slightly more likely than men to react to weather changes.
People have different reactions to changes. Some people feel slight discomfort that easily goes away on their own after some time. Others require special medications to avoid exacerbation of any disease that may occur due to changing weather conditions.
People who are most prone to negative experiences during pressure changes are: the following groups of people:
- WITH various diseases lungs, which include bronchial asthma, obstructive and chronic bronchitis.
- With heart and vascular diseases, especially hypertension, hypotension, atherosclerosis, and other disorders.
- With brain diseases, rheumatic pathologies, diseases of the musculoskeletal system, especially osteochondrosis.
It is also believed that changes in weather conditions provoke allergy attacks. In completely healthy people, the changes usually do not have a pronounced effect.
People with weather dependence experience headaches, drowsiness, a feeling of fatigue, and pulse irregularities that are not observed under normal conditions. In this case, it is advised to consult a doctor to exclude the development of diseases of the heart and nervous system.
People with various diseases, in addition to headaches and fatigue, may experience discomfort in the joints, changes in blood pressure, numbness in lower limbs, muscle pain. In case of exacerbation of chronic diseases, you should take medications prescribed by your doctor.
What to do if you are weather dependent
If increased sensitivity to changing weather conditions is present, but there are no diseases leading to it, then the following recommendations will help you cope with unpleasant sensations.
In the morning, it is advised to take a contrast shower, then drink a cup of good coffee to keep yourself in good shape. It is recommended to drink more tea during the day. Better - green with lemon. It will be useful to do exercises, several times a day.
Towards evening it is advised to relax. Herbal teas and decoctions with honey, valerian infusion and other mild sedatives will help with this. It is recommended to go to bed early and eat less salty foods during the day.
The weight of air determines atmospheric pressure (1 m 3 of air weighs 1.033 kg). For every meter of the earth's surface, air presses with a force of 10033 kg. It is a column of air from sea level to the upper atmosphere. For comparison: a column of water of the same diameter would have a height of only 10 m. In other words, the own mass of air creates atmospheric pressure, the value of which per unit area corresponds to the mass of the air column located above it. In this case, a decrease in air in this column leads to a decrease (drop) in pressure, and an increase in air leads to an increase (increase) in pressure. Normal atmospheric pressure is taken to be air pressure at sea level at a latitude of 45° and at a temperature of 0°C. In this case, it presses on every 1 cm 2 of the earth's surface with a force of 1.033 kg, and the mass of this air is balanced by a mercury column 760 mm high. The principle of pressure measurement is based on this dependence. It is measured in millimeters (mm) of mercury (or millibars (mb): 1 mb = 0.75 mmHg) and in hectopascals (hPa), when 1 mm = = 1 hPa.
Atmospheric pressure is measured using barometers. There are two types of barometers: mercury and metal (or aneroid).
A mercury cup consists of a glass tube sealed at the top and immersed with the lower open end into a metal cup containing mercury. A column of mercury in a glass tube balances with its weight the air pressure acting on the mercury in the cup. When the pressure changes, the height of the mercury column also changes. These changes are recorded by the observer on a scale attached next to the glass tube of the barometer.
A metal barometer, or aneroid, consists of a hermetically sealed thin-walled corrugated metal box, inside which the air is rarefied. When the pressure changes, the walls of the box vibrate and are pressed in or out. These vibrations are transmitted by a system of levers to the arrow, which moves along a graduated scale.
Self-recording barometers called barographs are used to record changes in pressure. The operation of the barograph is based on the fact that the vibrations of the walls of the aneroid box are transmitted, which draws a line on the tape of the drum rotating around its axis.
Pressure on the globe can vary widely. Thus, the maximum value is 815.85 mm Hg. (1087 mb) was registered in winter in Turukhansk, the minimum is 641.3 mm Hg. (854 MB) - in “Nancy” over the ocean.
Pressure changes with altitude. It is generally accepted that the average value of atmospheric pressure is pressure above sea level - 1013 mb (760 mm Hg). As altitude increases, the air becomes more rarefied and the pressure decreases. In the lower layer of the troposphere to a height of 10 m it decreases by 1 mm Hg. for every 10 m, or 1 mb (hPa) for every 8 m. At an altitude of 5 km it is already two times less, 15 km - 8 times, 20 km - 18 times.
Atmospheric pressure changes continuously due to the change and movement of air. During the day it increases twice (in the morning and in the evening), and decreases twice (after noon and after midnight). Throughout the year, the maximum pressure is observed in winter, when the air is supercooled and compacted, and the minimum is observed in summer.
The distribution of atmospheric pressure over the earth's surface has a well-defined zonal character, which is due to uneven heating of the earth's surface, and consequently, changes in pressure. The change in pressure is explained by the movement of air. It is high where there is more air, low where the air leaves. When heated from the surface, the air rushes upward and the pressure on the warm surface decreases. But at altitude, the air cools, becomes denser and begins to fall to neighboring cold areas, where the pressure increases. Thus, heating and cooling of air from the Earth's surface is accompanied by its redistribution and pressure changes.
In equatorial latitudes, air temperatures are constantly high; the air, heating up, rises and moves away. Therefore in equatorial zone pressure is constantly low. In tropical latitudes, increased pressure is created as a result of air influx. Above the constantly cold surface of the poles (and) the pressure is increased, it is created by air coming from latitudes. At the same time, in temperate latitudes, the outflow of air forms a belt low blood pressure. As a result, belts of low (and two moderate) and high (two tropical and two polar) pressures are formed on Earth. Depending on the season, they shift somewhat towards the summer hemisphere (following the Sun).
Polar regions high pressure They expand in winter, contract in summer, but exist all year round. Low pressure belts persist throughout the year near and in the temperate latitudes of the southern hemisphere. The picture is different in the northern hemisphere. Here in winter, in temperate latitudes over the continents, the pressure increases greatly and the field low pressure as if “breaking”: it persists only over the oceans in the form of closed areas of low pressure - the Icelandic and Aleutian minima. But over the continents, where the pressure has noticeably increased, so-called winter maxima are formed: Asian (Siberian) and North American (Canadian). Summer in temperate latitudes northern hemisphere the low pressure field is restored. At the same time, a vast area of low pressure forms over Asia - the Asian Low.
In tropical latitudes - a belt of high pressure - the continents always warm up more than the oceans, and the pressure above them is lower. This causes subtropical maxima over the oceans: North (Azores), North Pacific, South Atlantic, South Pacific and Indian.
In other words, the Earth’s belts of high and low pressure, despite large-scale seasonal changes in their indicators, are quite stable formations.
Many people are subject to change in environment. A third of the population is affected by the attraction of air masses to the earth. Atmospheric pressure: the norm for humans, and how deviations from the indicators affect the general well-being of people.
Changes in the weather can affect a person's condition
What atmospheric pressure is considered normal for humans?
Atmospheric pressure is the weight of air that presses on the human body. On average, this is 1.033 kg per 1 cubic cm. That is, 10-15 tons of gas control our mass every minute.
The standard atmospheric pressure is 760 mmHg or 1013.25 mbar. Conditions in which the human body feels comfortable or adapted. In fact, an ideal weather indicator for any inhabitant of the Earth. In reality, everything is not like that.
Atmospheric pressure is not stable. Its changes are daily and depend on the weather, terrain, sea level, climate and even time of day. The vibrations are not noticeable to humans. For example, at night the mercury rises 1-2 notches higher. Minor changes do not affect your well-being healthy person. Changes of 5-10 or more units are painful, and sudden significant jumps are fatal. For comparison: loss of consciousness from altitude sickness occurs when pressure drops by 30 units. That is, at a level of 1000 m above the sea.
The continent and even an individual country can be divided into conventional areas with different average pressure levels. Therefore, the optimal atmospheric pressure for each person is determined by the region of permanent residence.
High air pressure has a negative effect on hypertensive patients
Such weather conditions are generous for strokes and heart attacks.
For people who are vulnerable to the vagaries of nature, doctors advise on such days to stay outside the active work zone and deal with the consequences of weather dependence.
Meteor dependence - what to do?
The movement of mercury by more than one division in 3 hours is a reason for stress in the strong body of a healthy person. Each of us feels such fluctuations in the form of headaches, drowsiness, and fatigue. More than a third of people suffer from weather dependence to varying degrees of severity. In the zone of high sensitivity, populations with diseases of the cardiovascular, nervous and respiratory system, aged people. How to help yourself if a dangerous cyclone is approaching?
15 ways to survive a weather cyclone
There's not a lot of new advice here. It is believed that together they alleviate suffering and teach the correct way of life in case of weather vulnerability:
- See your doctor regularly. Consult, discuss, ask for advice in case your health worsens. Always have prescribed medications on hand.
- Buy a barometer. It is more productive to track the weather by the movement of the mercury column, rather than by knee pain. This way you will be able to anticipate the approaching cyclone.
- Keep an eye on the weather forecast. Forewarned is forearmed.
- On the eve of a weather change, get enough sleep and go to bed earlier than usual.
- Adjust your sleep schedule. Provide yourself with a full 8 hours of sleep, getting up and falling asleep at the same time. This has a powerful restorative effect.
- Meal schedule is equally important. Maintain a balanced diet. Potassium, magnesium and calcium are essential minerals. Ban on overeating.
- Take vitamins in a course in spring and autumn.
- Fresh air, walks outside - light and regular exercise strengthens the heart.
- Don't overexert yourself. Putting off household chores is not as dangerous as weakening the body before a cyclone.
- Accumulate favorable emotions. A depressed emotional background fuels the disease, so smile more often.
- Clothes made from synthetic threads and fur are harmful due to static current.
- Keep folk remedies for relieving symptoms in a list in a visible place. It’s hard to remember a recipe for herbal tea or a compress when your temples are aching.
- Office workers in high-rise buildings suffer more often from weather changes. Take time off if possible, or better yet, change jobs.
- A long cyclone means discomfort for several days. Is it possible to go to a quiet region? Forward.
- Prevention at least a day before the cyclone prepares and strengthens the body. Do not give up!
Don't forget to take vitamins to improve your health
Atmosphere pressure- This is a phenomenon that is absolutely independent of man. Moreover, our body obeys it. What the optimal pressure should be for a person is determined by the region of residence. People with chronic diseases are especially susceptible to weather dependence.
All bodies in the Universe tend to attract each other. Large and massive ones have a higher force of attraction compared to small ones. This law is also inherent in our planet.
The Earth attracts to itself any objects that are on it, including the gas shell surrounding it -. Although air is much lighter than the planet, it has heavy weight and presses on everything that is on the earth's surface. This creates atmospheric pressure.
What is atmospheric pressure?
Atmospheric pressure refers to the hydrostatic pressure of the gas shell on the Earth and objects located on it. At different heights and in different corners globe it has different indicators, but at sea level the standard is considered to be 760 mm Hg.
This means that a column of air weighing 1.033 kg exerts pressure on a square centimeter of any surface. Accordingly, there is a pressure of more than 10 tons per square meter.
People learned about the existence of atmospheric pressure only in the 17th century. In 1638, the Tuscan Duke decided to decorate his gardens in Florence with beautiful fountains, but unexpectedly discovered that the water in the constructed structures did not rise above 10.3 meters.
Deciding to find out the reason for this phenomenon, he turned for help to the Italian mathematician Torricelli, who, through experiments and analysis, determined that air has weight.
How is atmospheric pressure measured?
Atmospheric pressure is one of the most important parameters of the gas shell of the Earth. Since it varies in different places, a special device is used to measure it - a barometer. An ordinary household appliance is a metal box with a corrugated base, in which there is no air at all.
When the pressure increases, this box contracts, and when the pressure decreases, on the contrary, it expands. Along with the movement of the barometer, a spring attached to it moves, which affects the needle on the scale.
Liquid barometers are used at weather stations. In them, pressure is measured by the height of a mercury column enclosed in a glass tube.
Why does atmospheric pressure change?
Since atmospheric pressure is created by overlying layers of gas, it changes as altitude increases. It can be influenced by both air density and the height of the air column itself. In addition, pressure varies depending on the location on our planet, since different areas of the Earth are located at different altitudes above sea level. 
From time to time over earth's surface Slowly moving areas of high or low pressure are created. In the first case they are called anticyclones, in the second - cyclones. On average, pressure readings at sea level range from 641 to 816 mmHg, although internal pressures can drop to 560 mmHg.
How does atmospheric pressure affect the weather?
The distribution of atmospheric pressure across the Earth is uneven, which is associated, first of all, with the movement of air and its ability to create so-called baric vortices.
In the northern hemisphere, clockwise air rotation leads to the formation of downward air currents (anticyclones), which bring clear or partly cloudy weather with a complete absence of rain and wind to a particular area.
If the air rotates counterclockwise, then rising vortices are formed above the ground, characteristic of cyclones, with heavy precipitation, heavy winds, and thunderstorms. In the southern hemisphere, cyclones move clockwise, anticyclones move counterclockwise.
What effect does atmospheric pressure have on humans?
Each person is pressed by an air column weighing from 15 to 18 tons. In other situations, such a weight could crush all living things, but the pressure inside our body is equal to atmospheric pressure, so at normal levels of 760 mm Hg we do not experience any discomfort.
If the atmospheric pressure is higher or lower than normal, some people (especially the elderly or sick) feel unwell, headache, note exacerbation of chronic diseases.
Most often, a person experiences unpleasant sensations at high altitudes (for example, in the mountains), since in such areas the air pressure is lower than at sea level.
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