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Topic: Do-it-yourself physics instruments and simple experiments with them.

The work was completed by: 9th grade student - Davydov Roma Supervisor: physics teacher - Khovrich Lyubov Vladimirovna

Novouspenka - 2008

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Make a device, installation in physics to demonstrate physical phenomena with your own hands. Explain the principle of operation of this device. Demonstrate the operation of this device.

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HYPOTHESIS:

The made device, installation in physics for demonstrating physical phenomena with your own hands, apply in the lesson. In the absence of this device in the physical laboratory, this device will be able to replace the missing installation when demonstrating and explaining the topic.

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Make devices that are of great interest to students. Make devices missing from the laboratory. to make devices that cause difficulty in understanding theoretical material in physics.

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With uniform rotation of the handle, we see that the action of a periodically changing force will be transmitted to the load through the spring. Changing with a frequency equal to the frequency of rotation of the handle, this force will cause the load to make forced oscillations. Resonance is a phenomenon of a sharp increase in the amplitude of forced oscillations.

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EXPERIENCE 2: Jet Propulsion

We will install a funnel on a tripod in the ring, attach a tube with a tip to it. Pour water into the funnel, and when the water starts to flow from the end, the tube will deviate in the opposite direction. This is jet propulsion. Jet motion is the movement of a body that occurs when a part of it separates from it at any speed.

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EXPERIENCE 3: Sound waves.

Clamp a metal ruler in a vise. But it is worth noting that if most of the ruler acts as a vise, then, having caused its vibrations, we will not hear the waves generated by it. But if we shorten the protruding part of the ruler and thereby increase the frequency of its oscillations, then we will hear the generated Elastic waves propagating in the air, as well as inside liquid and solid bodies, they are not visible. However, under certain conditions they can be heard.

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Experience 4: Coin in a bottle

Coin in a bottle. Want to see the law of inertia in action? Prepare a half-liter milk bottle, a cardboard ring 25 mm wide and 0 100 mm wide and a two-kopeck coin. Place the ring on the neck of the bottle, and put a coin on top exactly opposite the opening of the bottle neck (Fig. 8). Inserting a ruler into the ring, hit it on the ring. If you do this abruptly, the ring will fly off and the coin will fall into the bottle. The ring moved so fast that its movement did not have time to be transferred to the coin and, according to the law of inertia, it remained in place. And having lost support, the coin fell down. If the ring is moved aside more slowly, the coin will “feel” this movement. The trajectory of its fall will change, and it will not fall into the neck of the bottle.

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Experience 5: A floating ball

When you blow, a jet of air lifts the balloon above the tube. But the air pressure inside the jet is less than the pressure of the “calm” air surrounding the jet. Therefore, the ball is in a kind of air funnel, the walls of which are formed by the surrounding air. By smoothly reducing the speed of the jet from the upper hole, it is not difficult to “land” the ball in its original place. For this experiment, you will need an L-shaped tube, such as glass, and a light foam ball. Close the top opening of the tube with a ball (Fig. 9) and blow into the side opening. Contrary to expectation, the ball will not fly off the tube, but will begin to hover above it. Why is this happening?

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Experience 6: The movement of the body along the "dead loop"

"Using the "dead loop" device, you can demonstrate a number of experiments on the dynamics of a material point along a circle. The demonstration is carried out in the following order: loop and flies out at a certain speed from the other end of the device 2. The ball is rolled up from the lowest height, when the ball only describes the loop without breaking off from its upper point 3. From an even lower height, when the ball, not reaching the top of the loop, breaks away from it and falls, describing a parabola in the air inside the loop.

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The movement of the body along the "dead loop"

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Experience 7: Air is hot and air is cold

Pull a balloon over the neck of an ordinary half-liter bottle (Fig. 10). Place the bottle in a pot of hot water. The air inside the bottle will begin to heat up. The molecules of the gases that make up it will move faster and faster as the temperature rises. They will bombard the walls of the bottle and the ball more strongly. The air pressure inside the bottle will begin to rise and the balloon will inflate. After a while, move the bottle into a pot of cold water. The air in the bottle will begin to cool, the movement of molecules will slow down, and the pressure will drop. The balloon will shrink as if the air has been sucked out of it. This is how you can see the dependence of air pressure on ambient temperature

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Experiment 8: Stretching a rigid body

Taking the foam bar by the ends, stretch it. One can clearly see the increase in the distances between the molecules. It is also possible to imitate the occurrence in this case of intermolecular forces of attraction.

Burdenkov Semyon and Burdenkov Yuri

Making a device with your own hands is not only a creative process that encourages you to show your ingenuity and ingenuity. In addition, during the manufacturing process, and even more so when demonstrating it in front of a class or the whole school, the manufacturer receives a lot of positive emotions. The use of home-made devices in the classroom develops a sense of responsibility and pride in the work done, proves its importance.

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Municipal state educational institution

Kukuy basic comprehensive school №25

Project

Do-it-yourself physical device

Completed by: 8th grade student

MKOU OOSH №25

Burdenkov Yu.

Head: Davydova G.A.,

Physics teacher.

1. Introduction.
2. Main part.

1. Purpose of the device;
2. tools and materials;
3. Device manufacturing;
4. General view of the device;

1. Conclusion.
2. Bibliography.

1. Introduction.

In order to put the necessary experience, you need to have instruments and measuring instruments. And do not think that all devices are made in factories. In many cases, research facilities are built by the researchers themselves. At the same time, it is considered that the most talented researcher is the one who can put experience and get good results not only on complex, but also on simpler instruments. Complex equipment is reasonable to use only in cases where it is impossible to do without it. So do not neglect home-made devices - it is much more useful to make them yourself than to use purchased ones.

GOAL:

Make a device, installation in physics to demonstrate physical phenomena with your own hands.

Explain the principle of operation of this device. Demonstrate the operation of this device.

TASKS:

Make devices that are of great interest to students.

Make devices missing from the laboratory.

Make devices that cause difficulty in understanding theoretical material in physics.

HYPOTHESIS:

The made device, installation in physics for demonstrating physical phenomena with your own hands, apply in the lesson.

In the absence of this device in the physical laboratory, this device will be able to replace the missing installation when demonstrating and explaining the topic.

1. Main part.

1. Purpose of the device.

The device is designed to observe the expansion of air and liquid when heated.

1. Tools and materials.

Ordinary bottle, rubber stopper, glass tube, the outer diameter of which is 5-6mm. Drill.

1. Device manufacturing.

Make a hole in the cork with a drill so that the tube fits snugly into it. Next, pour tinted water into the bottle to make it easier to observe. We put a scale on the neck. Then insert the cork into the bottle so that the tube in the bottle is below the water level. The device for the experiment is ready!

1. General view of the device.

1. Features of the demonstration of the device.

To demonstrate the device, you need to grab the neck of the bottle with your hand and wait a while. We will see that the water starts to rise up the tube. This happens because the hand heats the air in the bottle. When heated, the air expands, presses on the water and displaces it. The experiment can be done with different amounts of water, and you will find that the level of rise will be different. If the bottle is completely filled with water, then you can already observe the expansion of water when heated. To verify this, you need to lower the bottle into a vessel with hot water.

1. Conclusion.

It is interesting to watch the experience conducted by the teacher. Conducting it yourself is doubly interesting.

And to conduct an experiment with a device made and designed by one's own hands is of great interest to the whole class. In such experiments, it is easy to establish a relationship and draw a conclusion about how a given installation works.

1. Literature.

1. Teaching equipment for physics in high school. Edited by A.A. Pokrovsky "Enlightenment" 1973

Summary: Experience with a coin and a balloon. Entertaining physics for children. Fascinating physics. Do-it-yourself experiments in physics. Entertaining experiments in physics.

This experiment is a wonderful example of the action of centrifugal and centripetal force.

For the experience you will need:

Balloon (better than a pale color, so that when inflated it shines through as best as possible) - a coin - threads

Work plan:

1. Insert a coin inside the ball.

2. Inflate the balloon.

3. Tie it with thread.

4. Take the ball with one hand at the end where the thread is. Make several rotational movements with your hand.

5. After some time, the coin will begin to rotate in a circle inside the ball.

6. Now, with the second hand, fix the ball from below in a stationary position.

7. The coin will continue to spin for another 30 seconds or more.

Explanation of experience:

When an object rotates, there is a force called centrifugal. Have you been on a carousel? You felt a force throwing you outward from the axis of rotation. This is centrifugal force. When you spin the ball, centrifugal force acts on the coin, which presses it against the inside surface of the ball. At the same time, the ball itself acts on it, creating a centripetal force. The interaction of these two forces causes the coin to rotate in a circle.

Fomin Daniel

Physics is an experimental science and the creation of devices with one's own hands contributes to a better assimilation of laws and phenomena. Many different questions arise in the study of each topic. Many can be answered by the teacher himself, but how wonderful it is to get answers through your own independent research.

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DISTRICT SCIENTIFIC CONFERENCE OF STUDENTS

SECTION "Physics"

Project

Do-it-yourself physical device.

8th grade student

GBOU secondary school No. 1 town. Sukhodol

Sergievsky district of the Samara region

Scientific adviser: Shamova Tatyana Nikolaevna

Physics teacher

1. Introduction.

1. Main part.

1. Purpose of the device;
2. tools and materials;
3. Device manufacturing;
4. General view of the device;
5. Features of the demonstration of the device.

3.Research.

4. Conclusion.

5. List of used literature.

1. Introduction.

In order to put the necessary experience, you need to have instruments and measuring instruments. And do not think that all devices are made in factories. In many cases, research facilities are built by the researchers themselves. At the same time, it is considered that the most talented researcher is the one who can put experience and get good results not only on complex, but also on simpler instruments. Complex equipment is reasonable to use only in cases where it is impossible to do without it. So do not neglect home-made devices - it is much more useful to make them yourself than to use purchased ones.

GOAL:

Make a device, installation in physics to demonstrate physical phenomena with your own hands.

Explain the principle of operation of this device. Demonstrate the operation of this device.

TASKS:

Make devices that are of great interest to students.

Make devices missing from the laboratory.

Make devices that cause difficulty in understanding theoretical material in physics.

Investigate the dependence of the period on the length of the thread and the amplitude of the deflection.

HYPOTHESIS:

The made device, installation in physics for demonstrating physical phenomena with your own hands, apply in the lesson.

In the absence of this device in the physical laboratory, this device will be able to replace the missing installation when demonstrating and explaining the topic.

2. The main part.

2.1. Purpose of the device.

The device is designed to observe resonance in mechanical vibrations.

2.2.Tools and materials.

Ordinary wire, balls, nuts, tin, fishing line. Soldering iron.

2.3. Manufacture of the device.

Bend the wire into a support. Stretch the common line. Solder the balls to the nuts, measure the fishing line 2 pieces of the same length, the rest should be shorter and longer by a few centimeters, hang the balls with their help. Make sure that pendulums with the same line length do not end up next to each other. The device for the experiment is ready!

2.4. General view of the device.

2.5.Features of the demonstration of the device.

To demonstrate the device, it is necessary to choose a pendulum, the length of which coincides with the length of one of the three remaining ones, if you deviate the pendulum from the equilibrium position and leave it to itself, then it will oscillate freely. This will cause the fishing line to oscillate, as a result of which a driving force will act on the pendulums through the suspension points, periodically changing in magnitude and direction with the same frequency as the pendulum oscillates. We will see that a pendulum with the same suspension length will begin to oscillate with the same frequency, while the amplitude of oscillation of this pendulum is much greater than the amplitudes of the other pendulums. In this case, the pendulum oscillates in resonance with pendulum 3. This happens because the amplitude of the steady oscillations caused by the driving force reaches its maximum value precisely when the frequency of the changing force coincides with the natural frequency of the oscillatory system. The fact is that in this case the direction of the driving force at any moment of time coincides with the direction of motion of the oscillating body. Thus, the most favorable conditions are created for replenishing the energy of the oscillatory system due to the work of the driving force. For example, in order to swing the swing harder, we push it in such a way that the direction of the acting force coincides with the direction of the swing. But it should be remembered that the concept of resonance is applicable only to forced oscillations.

3. Thread or mathematical pendulum

Hesitations! Our gaze falls on the pendulum of the wall clock. Restlessly he hurries in one direction, then in the other, with his blows, as it were, breaking the flow of time into precisely measured segments. “One-two, one-two,” we involuntarily repeat to the beat of his ticking.

The plumb line and the pendulum are the simplest of all instruments used by science. It is all the more surprising that truly fabulous results have been obtained with such primitive tools: thanks to them, a person has managed to penetrate mentally into the bowels of the Earth, to find out what is happening tens of kilometers under our feet.

Swinging to the left and back to the right, to its original position, is a full swing of the pendulum, and the time of one full swing is called the period of oscillation. The number of vibrations of a body per second is called the vibration frequency. A pendulum is a body suspended from a thread, the other end of which is fixed. If the length of the thread is large compared to the dimensions of the body suspended on it, and the mass of the thread is negligible compared to the mass of the body, then such a pendulum is called a mathematical or thread pendulum. An almost small heavy ball suspended on a light long thread can be considered a thread pendulum.

The period of oscillation of the pendulum is expressed by the formula:

T \u003d 2π √ l / g

It can be seen from the formula that the period of oscillation of the pendulum does not depend on the mass of the load, the amplitude of oscillations, which is especially surprising. After all, with different amplitudes, an oscillating body travels different paths in one oscillation, but the time spent on this is always the same. The duration of the swing of the pendulum depends on its length and the acceleration of free fall.

In our work, we decided to test experimentally that the period does not depend on other factors and to verify the validity of this formula.

Study of the dependence of pendulum oscillations on the mass of the oscillating body, the length of the thread and the magnitude of the initial deflection of the pendulum.

Study.

Devices and materials: stopwatch, measuring tape.

The oscillation period of the pendulum was measured first for a body mass of 10 g and a deflection angle of 20°, while changing the length of the thread.

The period was also measured by increasing the deviation angle to 40°, with a mass of 10 g and different lengths of the thread. The measurement results were entered into the table.

Table.

From experiments, we have seen that the period does not really depend on the mass of the pendulum and the angle of its deflection, but with an increase in the length of the pendulum thread, the period of its oscillation will increase, but not in proportion to the length, but more difficult. The results of the experiments are shown in the table.

So, the period of oscillation of a mathematical pendulum depends only on the length of the pendulum l and from free fall acceleration g.

4. Conclusion.

It is interesting to watch the experience conducted by the teacher. Conducting it yourself is doubly interesting.

And to conduct an experiment with a device made and designed by one's own hands is of great interest to the whole class. ATsuch experiments, it is easy to establish the relationship and draw a conclusion about how this installation works.

5. Literature.

1. Teaching equipment for physics in high school. Edited by A.A. Pokrovsky "Enlightenment" 1973

2. Textbook on physics by A. V. Peryshkina, E. M. Gutnik "Physics" for grade 9;

3. Physics: Reference materials: O.F. Kabardin Textbook for students. - 3rd ed. - M.: Enlightenment, 1991.

Introduction

Without a doubt, all our knowledge begins with experience.
(Kant Emmanuel. German philosopher 1724-1804)

Physical experiments in an entertaining way introduce students to the various applications of the laws of physics. Experiments can be used in the classroom to draw students' attention to the phenomenon being studied, when repeating and consolidating educational material, and at physical evenings. Entertaining experiments deepen and expand students' knowledge, contribute to the development of logical thinking, instill interest in the subject.

This paper describes 10 entertaining experiments, 5 demonstration experiments using school equipment. The authors of the works are students of the 10th grade of the MOU secondary school No. 1 of the village of Zabaikalsk, Zabaikalsky Krai - Chuguevsky Artyom, Lavrentiev Arkady, Chipizubov Dmitry. The guys independently did these experiments, summarized the results and presented them in the form of this work.

The role of experiment in the science of physics

That physics is a young science
Can't say for sure here.
And in ancient times knowing science,
Always strive to get it.

The purpose of teaching physics is specific,
To be able to apply all knowledge in practice.
And it is important to remember - the role of the experiment
Must be in the first place.

Know how to plan and execute experiments.
Analyze and bring to life.
Build a model, put forward a hypothesis,
Strive to reach new heights

The laws of physics are based on facts established by experience. Moreover, the interpretation of the same facts often changes in the course of the historical development of physics. Facts accumulate as a result of observations. But at the same time, they cannot be limited only to them. This is only the first step towards knowledge. Next comes the experiment, the development of concepts that allow qualitative characteristics. In order to draw general conclusions from observations, to find out the causes of phenomena, it is necessary to establish quantitative relationships between quantities. If such a dependence is obtained, then a physical law is found. If a physical law is found, then there is no need to set up an experiment in each individual case, it is enough to perform the appropriate calculations. Having studied experimentally the quantitative relationships between the quantities, it is possible to identify patterns. Based on these regularities, a general theory of phenomena is developed.

Therefore, without experiment there can be no rational teaching of physics. The study of physics involves the widespread use of the experiment, the discussion of the features of its formulation and the observed results.

Entertaining experiments in physics

The description of the experiments was carried out using the following algorithm:

1. Name of experience
2. Instruments and materials necessary for the experiment
3. Stages of the experiment
4. Explanation of experience

Experience #1 Four floors

Equipment and materials: glass, paper, scissors, water, salt, red wine, sunflower oil, colored alcohol.

Stages of the experiment

Let's try to pour four different liquids into a glass so that they do not mix and stand one above the other in five floors. However, it will be more convenient for us to take not a glass, but a narrow glass expanding towards the top.

1. Pour salted tinted water into the bottom of a glass.
2. Roll out “Funtik” paper and bend its end at a right angle; cut off its tip. The hole in the Funtik should be the size of a pinhead. Pour red wine into this cone; a thin stream should flow out of it horizontally, break against the walls of the glass and flow down it into salt water.
   When the layer of red wine is equal in height to the height of the layer of tinted water, stop pouring the wine.
3. From the second cone, pour sunflower oil into a glass in the same way.
4. Pour a layer of colored alcohol from the third horn.

Picture 1

So we got four floors of liquids in one glass. All different colors and different densities.

Explanation of experience

The liquids in the groceries were arranged in the following order: tinted water, red wine, sunflower oil, tinted alcohol. The heaviest are at the bottom, the lightest are at the top. Salt water has the highest density, tinted alcohol has the smallest.

Experience #2 Amazing Candlestick

Devices and materials: a candle, a nail, a glass, matches, water.

Stages of the experiment

Isn't it an amazing candlestick - a glass of water? And this candlestick is not bad at all.

Figure 2

1. Weight the end of the candle with a nail.
2. Calculate the size of the nail so that the candle is completely immersed in water, only the wick and the very tip of the paraffin should protrude above the water.
3. Light the fuse.

Explanation of experience

Let me, they will tell you, because in a minute the candle will burn down to water and go out!

That's just the point, - you will answer, - that the candle is getting shorter every minute. And if it's shorter, it's easier. If it's easier, then it will float.

And, true, the candle will gradually float up, and the paraffin cooled by water at the edge of the candle will melt more slowly than the paraffin surrounding the wick. Therefore, a rather deep funnel is formed around the wick. This emptiness, in turn, lightens the candle, and that is why our candle will burn out to the end.

Experience No. 3 Candle behind a bottle

Equipment and materials: candle, bottle, matches

Stages of the experiment

1. Put a lit candle behind the bottle, and stand yourself so that your face is 20-30 cm away from the bottle.
2. It is worth now to blow, and the candle will go out, as if there is no barrier between you and the candle.

Figure 3

Explanation of experience

The candle goes out because the bottle is “flown around” with air: the jet of air is broken by the bottle into two streams; one flows around it on the right, and the other on the left; and they meet approximately where the flame of a candle stands.

Experience number 4 Spinning snake

Tools and materials: thick paper, candle, scissors.

Stages of the experiment

1. Cut a spiral out of thick paper, stretch it a little and put it on the end of the bent wire.
2. Holding this coil over the candle in an updraft of air will cause the snake to spin.

Explanation of experience

The snake rotates because there is an expansion of air under the action of heat and the transformation of warm energy into motion.

Figure 4

Experience No. 5 Eruption of Vesuvius

Devices and materials: glass vessel, vial, cork, alcohol ink, water.

Stages of the experiment

1. In a wide glass vessel filled with water, put a vial of alcohol ink.
2. There should be a small hole in the stopper of the vial.

Figure 5

Explanation of experience

Water has a higher density than alcohol; it will gradually enter the vial, displacing the mascara from there. Red, blue or black liquid will rise in a thin stream from the bubble up.

Experiment No. 6 Fifteen matches on one

Equipment and materials: 15 matches.

Stages of the experiment

1. Put one match on the table, and 14 matches across it so that their heads stick up and the ends touch the table.
2. How to lift the first match, holding it by one end, and with it all the other matches?

Explanation of experience

To do this, you only need to put one more, fifteenth match on top of all the matches, in the hollow between them.

Figure 6

Experience No. 7 Pot stand

Equipment and materials: a plate, 3 forks, a napkin ring, a saucepan.

Stages of the experiment

1. Put three forks in the ring.
2. Put a plate on this design.
3. Place a pot of water on a stand.

Figure 7

Figure 8

Explanation of experience

This experience is explained by the rule of leverage and stable equilibrium.

Figure 9

Experience No. 8 Paraffin motor

Devices and materials: a candle, a knitting needle, 2 glasses, 2 plates, matches.

Stages of the experiment

To make this motor, we don't need electricity or gasoline. We need only ... a candle for this.

1. Heat the needle and stick it with their heads into the candle. This will be the axis of our engine.
2. Put the candle with a knitting needle on the edges of two glasses and balance.
3. Light the candle at both ends.

Explanation of experience

A drop of paraffin will fall into one of the plates placed under the ends of the candle. The balance will be disturbed, the other end of the candle will pull and fall; at the same time, a few drops of paraffin will drain from it, and it will become lighter than the first end; it rises to the top, the first end will fall, drop a drop, it will become easier, and our motor will start to work with might and main; gradually fluctuations of the candle will increase more and more.

Figure 10

Experience No. 9 Free exchange of fluids

Equipment and materials: orange, glass, red wine or milk, water, 2 toothpicks.

Stages of the experiment

1. Carefully cut the orange in half, peel so that the skin is removed by a whole cup.
2. Poke two holes in the bottom of this cup side by side and put it in a glass. The diameter of the cup should be slightly larger than the diameter of the central part of the glass, then the cup will stay on the walls without falling to the bottom.
3. Lower the orange cup into the vessel one third of the height.
4. Pour red wine or colored alcohol into an orange peel. It will pass through the hole until the level of the wine reaches the bottom of the cup.
5. Then pour water almost to the brim. You can see how a stream of wine rises through one of the holes to the level of the water, while the heavier water passes through the other hole and begins to sink to the bottom of the glass. In a few moments the wine will be at the top and the water at the bottom.

Experience No. 10 Singing glass

Equipment and materials: a thin glass, water.

Stages of the experiment

1. Fill a glass with water and wipe the rim of the glass.
2. With a moistened finger, rub anywhere in the glass, she will sing.

Figure 11

Demonstration Experiments

1. Diffusion of liquids and gases

Diffusion (from Latin diflusio - spreading, spreading, scattering), the transfer of particles of different nature, due to the chaotic thermal motion of molecules (atoms). Distinguish between diffusion in liquids, gases and solids

Demonstration experiment "Observation of diffusion"

Devices and materials: cotton wool, ammonia, phenolphthalein, a device for observing diffusion.

Stages of the experiment

1. Take two pieces of cotton wool.
2. We moisten one piece of cotton wool with phenolphthalein, the other with ammonia.
3. Let's bring the branches together.
4. There is a pink staining of the fleece due to the phenomenon of diffusion.

Figure 12

Figure 13

Figure 14

The phenomenon of diffusion can be observed using a special installation

1. Pour ammonia into one of the cones.
2. Moisten a piece of cotton wool with phenolphthalein and put it on top in a flask.
3. After a while, we observe the coloring of the fleece. This experiment demonstrates the phenomenon of diffusion at a distance.

Figure 15

Let us prove that the phenomenon of diffusion depends on temperature. The higher the temperature, the faster diffusion proceeds.

Figure 16

To demonstrate this experiment, let's take two identical glasses. Pour cold water into one glass, hot water into the other. We add copper sulphate to glasses, we observe that copper sulphate dissolves faster in hot water, which proves the dependence of diffusion on temperature.

Figure 17

Figure 18

2. Communicating vessels

To demonstrate communicating vessels, let us take a number of vessels of various shapes, connected at the bottom by tubes.

Figure 19

Figure 20

We will pour liquid into one of them: we will immediately find that the liquid will flow through the tubes into the remaining vessels and will settle in all vessels at the same level.

The explanation for this experience is as follows. The pressure on the free surfaces of the liquid in the vessels is the same; it is equal to atmospheric pressure. Thus, all free surfaces belong to the same level surface and, therefore, must be in the same horizontal plane and the upper edge of the vessel itself: otherwise the kettle cannot be filled to the top.

Figure 21

3. Pascal's ball

Pascal's ball is a device designed to demonstrate the uniform transfer of pressure exerted on a liquid or gas in a closed vessel, as well as the rise of a liquid behind a piston under the influence of atmospheric pressure.

To demonstrate the uniform transmission of pressure produced on a liquid in a closed vessel, it is necessary, using a piston, to draw water into the vessel and tightly fit a ball onto the nozzle. By pushing the piston into the vessel, demonstrate the outflow of liquid from the holes in the ball, paying attention to the uniform outflow of liquid in all directions.