How is the atmospheric pressure of the air calculated? 5

Measured by the height of mercury,

The formula for calculating the pressure is p=f s, where p represents the pressure, f represents the vertical force (pressure), and s represents the area of the force. Secondly, the pressure formula of the liquid column also has p= gh, where , denotes the density of the liquid, g is the acceleration due to gravity, and h denotes the depth of the liquid

Pressure is a physical quantity that expresses the magnitude of the force exerted on an object per unit area. The standard atmospheric pressure is to the 5th power) Pa, the value of the large lead Qi pressure is equivalent to the pressure generated by the mercury column of about 76 cm, which is the magnitude of the atmospheric pressure.

Methods for decreasing and increasing pressure1. Methods for reducing pressure.

1. When the pressure f is constant, increase the stress area s;

2. When the stress area S is constant, reduce the pressure f;

3. At the same time, reduce the pressure f and increase the stress area s.

Second, the method of increasing the pressure.

1. When the pressure f is constant, reduce the stress area S;

2. When the stress area S is constant, increase the pressure and regret force f;

3. Increase the pressure f and decrease the stress area s at the same time.

Flow velocity Cross-sectional area (pressure 10 1) (t 20) (t t).

There are two types of measuring instruments commonly used in meteorology: liquid (such as mercury) barometer and solid (such as metal empty box) barometer. Barometric pressure recordings are measured by a barometer or barometer installed in a well-lit baropressure chamber with little variation in temperature.

There are timed air pressure records and continuous records of hail pressure in the flutter wheel. The timed pressure record of manual visual measurement is measured by a moving trough or fixed trough mercury barometer, and the basic station observes 4 times a day and the base station observes 24 times a day.

In a high-pressure environment, the tissues of the body are gradually saturated with nitrogen (generally after 5-6 hours of working under high pressure, the human body is saturated with nitrogen), and when the human body returns to the standard atmospheric pressure, the excess nitrogen in the body will be exhaled with exhalation, but this process is relatively slow.

If you suddenly return to the standard barometric environment from a high-pressure environment, some of the nitrogen accumulated in the fat may stay in the body and swell to form small bubbles, blocking blood and tissues, and easily forming air embolism and causing diseases, which will endanger people's lives in severe cases.

The impact of air pressure changes on human health is more manifested in the generation, disappearance or movement of the circulating weather situation represented by high pressure or low pressure. Under the low-pressure circulation manifold sail potential, most of the weather is cloudy and rainy, and the wind changes are obvious. In the situation of high-pressure circulation, it is mostly sunny and the weather is relatively stable.

Indicates the single Chang bucket position of air pressure, and it is customary to use the height of the mercury column. For example, a standard atmospheric pressure is equal to the weight of a 760 millimeter-high column of mercury, which is equivalent to the atmospheric pressure of a kilogram on an area of one square centimeter.

SI Medium Pressure Spike Strength Unit: 1Pa=1N m 2 Other Units: Standard Atmospheric Pressure ATM, 1ATM= Torr, 1Torr= Engineering Atmospheric Pressure AT, 1AT= kgf M 2 1kgf M 2= mm Changxunbu Mercury Column MMHG, 1mmHg= The above conversion is based on gravitational acceleration.

1 standard atmosphere = 760 mm Hg = 76 cm Hg = Pascal = meter water column.

Standard atmospheric pressure, the pressure at sea level under standard atmospheric conditions, the value of which is, is a unit of pressure, denoted as atm. That is, it can be seen approximately. 1 standard atmospheric pressure = 760 mm Hg = 76 cm Hg = water bar.

The formula for gas pressure is PV=Nrt (P is the gas pressure, V is the volume, N is the quantity of matter, R is the constant, and T is the Kelvin temperature).

The deformation formula is: pm= rt; pv=mrt/m。

Atmospheric pressure definition.

Atmospheric pressure refers to the pressure produced by the air at a certain location on the earth. The air on the surface of the earth is subjected to gravity, which produces atmospheric pressure, and the density of the air layer above the earth is not equal, the air near the surface layer is denser, and the air in the upper layers is thin and less dense.

Since the atmospheric pressure is generated by the gravity of the air, where the height is large, the height of the air column above it is small, and the density is also small, so the higher the distance from the ground, the smaller the atmospheric pressure Normally, below 2 kilometers, for every 12 meters of altitude, the atmospheric pressure decreases by 1 millimeter of mercury.

Both gases and liquids are fluid, and their pressures are similar, the atmospheric pressure is in all directions, and the atmospheric pressure in all directions is equal at the same location. But since the density of the atmosphere is not uniform, the liquid pressure formula cannot be applied to the calculation of atmospheric pressure.