We are surrounded by the atmosphere, and the pressure is great, and the pressure is great.

Fill the cup with water and cover it with paper, so there is water between the cup and the hard paper, and there is almost no air in the quilt. The external atmospheric pressure presses the paper tightly on the cup, so the water can't flow down.

The sea level pressure at 0℃ and latitude of 45 degrees is called 1 atmospheric pressure, and the value on the mercury barometer is 760mm mercury column height (equivalent to 10 13.25 hectopascals). It is equivalent to bearing an atmospheric pressure of 1.0336 kg in an area of one square centimeter.

This pressure can increase the water column sealed in the air-free pipeline by about 10 meter, or increase the mercury by 76 cm.

After conversion: a standard atmospheric pressure =1.013x10 to the fifth power.

Physical formula? Pressure = pressure? zone

The atmospheric pressure outside is far greater than the gravity of water itself. So that the water in the paper won't break out.

Extended data

1640 10 Torricelli, assistant of Torricelli Galileo, realized that the weight of air in the atmosphere exerted pressure on the mercury in the basin, and this force pressed the mercury into the glass tube.

The weight of mercury in the glass tube should be exactly equal to the weight of mercury exerted by the atmosphere on the basin. When the weight of the atmosphere changes, the pressure it exerts on the basin will increase or decrease, thus causing the mercury column in the glass tube to rise or fall. Weather changes will inevitably cause changes in the weight of the atmosphere.

Torricelli discovered atmospheric pressure and found a way to measure and study it. Torricelli's discovery was the beginning of a formal study of weather and atmosphere, which made us understand the atmosphere and laid the foundation for Newton and other scientists to study gravity.

At the same time, this new discovery made Torricelli create the concept of vacuum and invented the basic instrument of meteorological research-barometer.

Application of atmospheric pressure:

Press a plastic hook with a sucker on a very flat wall, and you can hang things with it.

Piston and centrifugal pumps can pump water from the lower part to the higher part.

Squeeze the air out of the pen tube, and then let go to suck the ink into the pen tube.

Cooking food in a pressure cooker is easy.

Make a small hole in the tea cover so that the water can be poured out easily.

There are also high-pressure boilers, agricultural sprayers, drinking water through straws, and using syringe needles for liquid medicine, all of which are related to atmospheric pressure.

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