About the atmospheric pressure experiment. A little experiment on atmospheric pressure

1 egg is sucked into the bottle.

Principle: The oxygen consumption in the bottle causes the air pressure inside the bottle to be less than the outside air pressure, and the egg enters the bottle under the action of atmospheric pressure.

2. Principle, the air pressure inside the hemisphere is much smaller than the external air pressure after the air is pumped out, and the two hemispheres are close together under the action of atmospheric pressure.

3. After the air in the box is pumped out, the air pressure is much less than the external air pressure, and the box body is deformed inward under the action of external atmospheric pressure.

1 Phenomenon The egg is sucked into the bottle Reason The burning of alcohol cotton consumes the oxygen in the bottle so that the internal air pressure is small and the external air pressure is large, and the egg is pressed into the pressure bottle by the atmosphere due to the atmospheric pressure.

2 Phenomenon The hemisphere is not pulled apart Reason The air pressure in the ball is small Due to the atmospheric pressure, the hemisphere is not pulled apart.

3. The empty beverage box is deflated due to the fact that there is less air in the box, so that the air pressure in the box is small, and the empty beverage box is deflated due to atmospheric pressure.

Give it points!

1.The egg is pressed in, because the gas in the bottle expands and contracts after combustion, the air pressure becomes smaller, and the egg is pressed in.

2.There is a book on it, 3The lungs get bigger, the air pressure gets smaller, so the air is pushed out.

The eggs are pressed into the bottle by atmospheric pressure because the outside atmospheric pressure is large and the inside of the bottle is small.

You can't kick off the ball because it's close to a vacuum inside the ball.

The empty beverage carton becomes deflated because the outside atmospheric pressure is high and the inside of the bottle is small.

This is related to the amount of gas, filled with water but there is no guarantee that there will be no gas, this little air is negligible. And 1 2 is not enough water, too much air, and the internal pressure of the cup is stronger than the external pressure, so it will not succeed.

Cover the glass filled with water with paper so that the water does not leak when it is turned upside down.

There are many small experiments on atmospheric pressure, and some of them are easy to draw from and simple to process. Here are some of the experiments on atmospheric pressure:

1. Preparation materials: 1 basin, 1 transparent glass cup, a candle (slightly shorter), water (red pen water can be added to the water, the vision is obvious).

The process of deferring the actual residue base: fix the candle on the bottom of the pot with candle oil. Next, pour the water into the basin (don't extinguish the candle). Then, place the clear glass cup over the candle. After a while, the candle went out and the water in the cup rose.

The principle of the experiment: there is about 1 5 oxygen in the air, and the burning of the candle consumes oxygen, so that the air pressure inside the glass is lower than that of the outside other, so that the water is pressed into the cup. The water in the cup was raised.

2. Prepare materials: a small suction cup, a thicker needle or awl, and appropriate weights.

Experimental process: Squeeze out the air with a small suction cup and stick it on a relatively flat wall. As a result, heavy objects can be lifted without external force, and then a small hole is poked in the surface of the plate at the end, and the small suction cup falls off immediately.

Experimental principle: the suction cup squeezes out the bright air, due to the atmospheric pressure, so that the suction cup can lift heavy objects, if the disc surface pokes a small hole, the air enters, the internal and external pressure is balanced, and the suction cup falls off, thus proving the existence of atmospheric pressure.

3. Prepare materials: a glass cup with a flat mouth, a flat piece of cardboard, and a few waters.

Experimental process: fill the glass with water, still use the cardboard lid to the mouth of the glass, hold it down with your hand, and turn it upside down (cup covering experiment): the glass is filled with water, the air is discharged, the pressure of the water in the cup on the cardboard is less than the atmospheric pressure, and the hard vertical mold paper is supported under the action of atmospheric pressure.

And when the rim of the cup is turned in a circle in all directions, the piece of cardboard does not fall off.

Experimental principle: There is atmospheric pressure, and the atmosphere has pressure in all directions.

4. Prepare materials: a small test tube and a few waters.

Experimental process: Immerse the small-caliber test tube in water, fill it with water and lift it upside down to the surface of the water, and the water will not flow out.

Experimental principle: the role of atmospheric pressure.

The experimental procedure for measuring the barometric pressure of the big selling circle is as follows:

1. Experimental process: fill the glass tube with a length of about 1m and closed at one end with mercury, block the nozzle, and then insert it inverted into the mercury tank to release the finger blocking the nozzle, the mercury surface in the tube will not fall if it drops some, and the height difference between the inside and outside of the tube is about 760mm.

2. Principle analysis: take a liquid sheet in the pipe, which is level with the liquid level outside the pipe, and the liquid sheet is balanced by the pressure up and down because the liquid is not moving. That is, the upward atmospheric pressure = the pressure generated by the mercury column.

3. Conclusion: atmospheric pressure p0 = 760 mmHg = 76 cmHg = its value changes with the change of auspicious collapse in the external atmospheric pressure).

4. Description: The purpose of filling the glass tube with mercury before the experiment is: after the glass tube is inverted, the mercury is above the vacuum; If it is not filled, the measurement result is on the low side.

In this experiment, if mercury is changed to water, a glass tube with a length of m is required

The glass tube is slightly lifted or pressed down, the height difference between the inside and outside of the tube remains unchanged, and the glass tube is tilted, the height remains the same, and the length becomes longer.

If the outside atmospheric pressure is h cmhg, try to write the pressure of the sealed gas (the liquid in the tube is mercury) in each of the following situations.

Experiments on atmospheric pressure.

Principle: There is atmospheric pressure around the A4 paper. The atmospheric pressure acts vertically on the surface of the A4 paper, so that it is tightly pressed against the tabletop, and the larger the surface area, the greater the atmospheric pressure is subjected to the rattle.

The various striking forces in the experiment were not enough to overcome the atmospheric pressure, so the A4 paper was not cocked by the ruler. But when the force of the blow is large enough to exceed the atmospheric pressure to which the A4 paper is subjected, the ruler will fall.

Expansion: Atmospheric pressure is the atmospheric pressure acting on a unit area, that is, the gravitational force that is numerically equal to the vertical column of air that extends upward to the upper boundary of the atmosphere per unit area. The famous Magdeburg hemispheric experiment proves its existence.

The international unit of air pressure is Pascal, abbreviated as Pa, and the symbol is Pa. In meteorology, people generally use kilopascal (kpa) or hectopar (hpa) as the unit. The other commonly used single-yearling slots are:

bar (1 bar = 100,000 Pa) and a centimeter of mercury (or centimeters of mercury). Air pressure varies not only with altitude but also with temperature. Changes in air pressure are closely related to weather changes.

There can be many kinds of this. A cup that automatically drinks water. Take a shallow plate, a glass, a small piece of tissue paper and matches.

Place the plate on the table and fill the plate with a small amount of water. If you fail, you will light the paper and quickly stuff it into the glass, and then immediately turn the rim downside down on the plate (pictured). As the fire goes out, the cup is like a thirsty and smoking throat, which makes the water in the dish "clear" and pure, and the water that enters the cup will not flow out again.

If you put a coin in the bottom of the tray beforehand, you can take it out without getting wet. Of course, when buckle the cup, be careful not to cover the coin with the rim. Note that you should not put too much water in the plate, otherwise you may not be able to drink the water in the bowl of the ear stall.

Who rises in an inverted beaker.

Measure atmospheric pressure with a bicycle inflate.

Air flatten the canning box.

Thread the straw through the potato.

Siphon fountain. Guess the heavy "newspaper."

The well-known test that can prove the presence of atmospheric pressure is:Magdeburg Hemispheric Experiment

Magdeburger Hemisphere (German: Magdeburger Halbkugeln, English: Magdeburg Hemisphere), also known as Magdeburg Hemisphere, was a scientific experiment conducted in 1654 by Otto von Glick, then mayor of Magdeburg, in Regensburg (present-day Regensburg, Germany), in the Holy Roman Empire in order to prove the existence of atmospheric pressure.

The experiment was also known as the "Magdeburg Hemisphere" experiment because of Glick's title. The two hemispheres in which the experiments were conducted are still preserved in the Deutsches Museum in Munich. In reality, there are also imitations for teaching purposes, used to demonstrate the principle of air pressure, and their volume is much smaller than that of the hemisphere of the year, so that the hemisphere space can be vacuumed, and there is no need for more than a dozen horses, and some can be pulled apart by only four people.

Magdeburg hemispheric experiments proved:Atmospheric pressure exists, and it is very strong. In the experiment, the air in the two hemispheres was pumped out, so that the number of air particles in the balls decreased and decreased.

The atmosphere outside the sphere compresses the two hemispheres together, so it is not easy to separate. The more air is removed, the greater the pressure on the hemispheres and the less likely it is for the two hemispheres to separate.

Experiments and phenomena of atmospheric pressure.

Magdeburg Hemispheric ExperimentBring the two hemispheres together, extract the air inside, and pull the two hemispheres on either side with the horses, and it took twelve horses to pull the ball apart. It proves that atmospheric pressure is not only present, but also great.

You can bring the two hemispheres together, extract the air inside, and pull them on both sides with horses, and it will take 12 horses to pull it apart.