Homemade physics instruments. Research work "Home-made devices for educational research in physics Do-it-yourself physics devices

Artificial tornado. In one of the books of N. E. Zhukovsky, the following installation is described for obtaining an artificial tornado. At a distance of 3 m above the vat of water, a hollow pulley with a diameter of 1 m is placed, having several radial partitions (Fig. 119). With the rapid rotation of the pulley, a spinning water tornado rises from the vat towards it. Explain the phenomenon. What is the reason for the formation of a tornado in nature?

"Universal barometer" by M. V. Lomonosov (Fig. 87). The instrument consists of a mercury-filled barometric tube with ball A on top. The tube is connected by capillary B to another ball containing dry air. The instrument is used to measure minute changes in atmospheric pressure force. Understand how this device works.

Device N. A. Lyubimov. Professor of Moscow University N. A. Lyubimov was the first scientist who experimentally investigated the phenomenon of weightlessness. One of his devices (Fig. 66) was a panel l with loops, which could fall along the guide vertical wires. On panel l a vessel with water is strengthened 2. Inside the vessel, with the help of a rod passing through the lid of the vessel, a large cork is placed 3. Water tends to push out the cork, and the latter, stretching the wire. 4, holding the index arrow on the right side of the screen. Will the pointer retain its position relative to the vessel if the instrument falls?

Do you love physics? You love experiment? The world of physics is waiting for you!
What could be more interesting than experiments in physics? And of course, the simpler the better!
These exciting experiences will help you see extraordinary phenomena light and sound, electricity and magnetism Everything you need for experiments is easy to find at home, and the experiments themselves simple and safe.
Eyes are burning, hands are itching!
Go explorers!

Robert Wood - the genius of experiments..........
- Up or down? Rotating chain. Salt fingers.......... - Moon and diffraction. What color is the fog? Rings of Newton.......... - Top in front of the TV. Magic propeller. Ping-pong in the bath.......... - Spherical aquarium - lens. artificial mirage. Soap glasses .......... - Eternal salt fountain. Fountain in a test tube. Spinning spiral .......... - Condensation in the bank. Where is the water vapor? Water engine.......... - A popping egg. Inverted glass. Whirlwind in a cup. Heavy paper..........
- Toy IO-IO. Salt pendulum. Paper dancers. Electric dance..........
- Ice Cream Mystery. Which water freezes faster? It's cold and the ice is melting! .......... - Let's make a rainbow. A mirror that does not confuse. Microscope from a drop of water
- Snow creaks. What will happen to the icicles? Snow flowers.......... - Interaction of sinking objects. The ball is touchy ..........
- Who quickly? Jet balloon. Air carousel .......... - Bubbles from the funnel. Green hedgehog. Without opening the bottles.......... - Candle motor. A bump or a hole? Moving rocket. Diverging Rings..........
- Multi-colored balls. Sea dweller. Balancing Egg..........
- Electric motor in 10 seconds. Gramophone..........
- Boil, cooling .......... - Waltzing dolls. Flames on paper. Robinson Feather..........
- Faraday experience. Segner wheel. Nutcrackers .......... - Dancer in the mirror. Silver plated egg. Trick with matches .......... - Oersted's experience. Roller coaster. Don't drop it! ..........

Body weight. Weightlessness.
Experiments with weightlessness. Weightless water. How to reduce your weight..........

Elastic force
- A jumping grasshopper. Jumping ring. Elastic coins..........
Friction
- Crawler coil..........
- A sunken thimble. Obedient ball. We measure friction. Funny monkey. Vortex rings..........
- Rolling and sliding. Friction of rest. Acrobat walks on a wheel. Brake in the egg..........
Inertia and inertia
- Get the coin. Experiments with bricks. Wardrobe experience. Experience with matches. coin inertia. Hammer experience. Circus experience with a jar. The ball experience....
- Experiments with checkers. Domino experience. Egg experience. Ball in a glass. Mysterious skating rink..........
- Experiments with coins. Water hammer. Outwit inertia..........
- Experience with boxes. Checkers experience. Coin experience. Catapult. Apple momentum..........
- Experiments with inertia of rotation. The ball experience....

Mechanics. Laws of mechanics
- Newton's first law. Newton's third law. Action and reaction. Law of conservation of momentum. Number of movement..........

Jet propulsion
- Jet shower. Experiments with reactive pinwheels: air pinwheel, jet balloon, ethereal pinwheel, Segner's wheel ..........
- Balloon rocket. Multistage rocket. Impulse ship. Jet boat..........

Free fall
- Which is faster..........

Circular motion
- Centrifugal force. Easier on turns. Ring experience....

Rotation
- Gyroscopic toys. Clark's wolf. Greig's wolf. Flying top Lopatin. Gyro machine ..........
- Gyroscopes and tops. Experiments with a gyroscope. Spinning Top Experience. Wheel experience. Coin experience. Riding a bike without hands. Boomerang Experience..........
- Experiments with invisible axes. Experience with staples. Matchbox rotation. Slalom on paper..........
- Rotation changes shape. Cool or raw. Dancing egg. How to strike a match..........
- When the water does not pour out. A little circus. Experience with a coin and a ball. When the water is poured out. Umbrella and separator..........

Statics. Equilibrium. Center of gravity
- Roly-ups. Mysterious matryoshka..........
- Center of gravity. Equilibrium. Center of gravity height and mechanical stability. Base area and balance. Obedient and naughty egg..........
- Human center of gravity. Fork balance. Funny swing. Diligent sawer. Sparrow on a branch..........
- Center of gravity. Pencil competition. Experience with unstable balance. Human balance. Stable pencil. Knife up. Cooking experience. Experience with a saucepan lid ..........

The structure of matter
- Fluid model. What gases does air consist of? The highest density of water. Density tower. Four floors..........
- Plasticity of ice. A popped nut. Properties of a non-Newtonian fluid. Growing crystals. Properties of water and egg shells..........

thermal expansion
- Expansion of a rigid body. Ground stoppers. Needle extension. Thermal scales. Separation of glasses. Rusty screw. Board to smithereens. Ball expansion. Coin Expansion..........
- Expansion of gas and liquid. Air heating. Sounding coin. Water pipe and mushrooms. Water heating. Snow heating. Dry from water. The glass is creeping..........

Surface tension of a liquid. wetting
- Plateau experience. Darling experience. Wetting and non-wetting. Floating razor..........
- Attraction of traffic jams. Adhesion to water. Miniature Plateau experience. Bubble..........
- Live fish. Experience with a paperclip. Experiments with detergents. Color streams. Rotating spiral ..........

Capillary phenomena
- Experience with a blooper. Experience with pipettes. Experience with matches. Capillary pump..........

Bubble
- Hydrogen soap bubbles. Scientific preparation. Bubble in a bank. Colored rings. Two in one..........

Energy
- Transformation of energy. Curved strip and ball. Tongs and sugar. Photoexposure meter and photoelectric effect ..........
- Transfer of mechanical energy into heat. Propeller experience. Bogatyr in a thimble..........

Thermal conductivity
- Experience with an iron nail. Tree experience. Glass experience. Spoon experience. Coin experience. Thermal conductivity of porous bodies. Thermal conductivity of gas ..........

Heat
- Which is colder. Heating without fire. Heat absorption. Radiation of heat. Evaporative cooling. Experience with an extinguished candle. Experiments with the outer part of the flame ..........

Radiation. Energy transfer
- Transfer of energy by radiation. Experiments with solar energy

Convection
- Weight - heat controller. Experience with stearin. Creating traction. Experience with weights. Spinner experience. Spinner on a pin..........

aggregate states.
- Experiments with soap bubbles in the cold. Crystallization
- Frost on the thermometer. Evaporation on the iron. We regulate the boiling process. instant crystallization. growing crystals. We make ice. Ice cutting. Rain in the kitchen....
- Water freezes water. Ice castings. We create a cloud. We make a cloud. We boil snow. Ice bait. How to get hot ice..........
- Growing crystals. Salt crystals. Golden crystals. Large and small. Peligo's experience. Experience is the focus. Metallic crystals..........
- Growing crystals. copper crystals. Fairy beads. Halite patterns. Home hoarfrost..........
- Paper bowl. Experience with dry ice. Experience with socks

Gas laws
- Experience on the Boyle-Mariotte law. Experiment on Charles' law. Let's check the Claiperon equation. Checking Gay-Lusac's law. Focus with a ball. Once again about the Boyle-Mariotte law ..........

Engines
- Steam engine. Experience of Claude and Bouchereau..........
- Water turbine. Steam turbine. Wind turbine. Water wheel. Hydro turbine. Windmills-toys..........

Pressure
- Solid body pressure. Punching a coin with a needle. Ice cutting..........
- Siphon - Tantalum vase..........
- Fountains. The simplest fountain Three fountains. Fountain in a bottle. Fountain on the table..........
- Atmosphere pressure. Bottle experience. Egg in a decanter. Bank sticking. Glass experience. Canister experience. Experiments with a plunger. Bank flattening. Experience with test tubes..........
- A blotter vacuum pump. Air pressure. Instead of the Magdeburg hemispheres. Glass-diving bell. Carthusian diver. Punished curiosity..........
- Experiments with coins. Egg experience. Newspaper experience. School gum suction cup. How to empty a glass..........
- Pumps. Spray..........
- Experiments with glasses. The mysterious property of the radish. Bottle experience..........
- Naughty cork. What is pneumatics. Experience with a heated glass. How to raise a glass with the palm of your hand..........
- Cold boiling water. How much water weighs in a glass. Determine the volume of the lungs. Persistent funnel. How to pierce a balloon so that it does not burst ..........
- Hygrometer. Hygroscope. Cone barometer .......... - Barometer. Do-It-Yourself Aneroid Barometer. Ball barometer. The simplest barometer .......... - Light bulb barometer .......... - Air barometer. water barometer. Hygrometer..........

Communicating vessels
- Experience with the picture..........

Law of Archimedes. Pulling force. Swimming bodies
- Three balls. The simplest submarine. Experience with grapes. Does iron float?
- Draft of the ship. Does the egg float? Cork in a bottle. Water candlestick. Sinking or floating. Especially for the drowning. Experience with matches. Amazing egg. Does the plate sink? The riddle of scales ..........
- A float in a bottle. Obedient fish. Pipette in a bottle - Cartesian diver..........
- Ocean level. Boat on the ground. Will the fish drown. Scales from a stick ..........
- Law of Archimedes. Live toy fish. Bottle level..........

Bernoulli's law
- Funnel experience. Water jet experience. Ball experience. Experience with weights. Rolling cylinders. stubborn sheets..........
- Bending sheet. Why doesn't he fall. Why does the candle go out. Why doesn't the candle go out? Blame the air flow..........

simple mechanisms
- Block. Polyspast ..........
- Lever of the second kind. Polyspast ..........
- Lever arm. Gate. Lever scales..........

fluctuations
- Pendulum and bicycle. Pendulum and the globe. Fun duel. Unusual pendulum ..........
- Torsional pendulum. Experiments with a swinging top. Rotating pendulum..........
- Experience with the Foucault pendulum. Addition of vibrations. Experience with Lissajous figures. Pendulum resonance. Hippo and bird..........
- Funny swing. Vibrations and Resonance ..........
- Fluctuations. Forced vibrations. Resonance. Seize the moment..........

Sound
- Gramophone - do it yourself ..........
- Physics of musical instruments. String. Magic bow. Ratchet. Drinking glasses. Bottlephone. From the bottle to the organ..........
- Doppler effect. sound lens. Chladni's experiments ..........
- Sound waves. Spreading sound..........
- Sounding glass. Straw flute. String sound. Reflection of sound..........
- Phone from a matchbox. Telephone exchange ..........
- Singing combs. Spoon call. Drinking glass..........
- Singing water. Scary wire..........
- Audio oscilloscope..........
- Ancient sound recording. Cosmic voices....
- Hear the beat of the heart. Ear glasses. Shock wave or clapperboard ..........
- Sing with me. Resonance. Sound through the bone..........
- Tuning fork. Storm in a glass. Louder sound..........
- My strings. Change the pitch. Ding Ding. Crystal clear..........
- We make the ball squeak. Kazu. Drinking bottles. Choral singing..........
- Intercom. Gong. Crow's glass..........
- Blow out the sound. Stringed instrument. Little hole. Blues on the bagpipe..........
- Sounds of nature. Drinking straw. Maestro, march..........
- A speck of sound. What's in the bag. Surface sound. Disobedience Day..........
- Sound waves. Visible sound. Sound helps to see ..........

Electrostatics
- Electrification. Electric coward. Electricity repels. Soap bubble dance. Electricity on combs. Needle - lightning rod. Electrification of the thread ..........
- Bouncing balls. Interaction of charges. Sticky ball..........
- Experience with a neon light bulb. Flying bird. Flying butterfly. Living world..........
- Electric spoon. Saint Elmo's fire. Water electrification. Flying cotton. Soap bubble electrization. Loaded frying pan..........
- Electrification of the flower. Experiments on the electrification of man. Lightning on the table..........
- Electroscope. Electric theater. Electric cat. Electricity attracts...
- Electroscope. Bubble. Fruit Battery. Gravity fight. Battery of galvanic elements. Connect the coils..........
- Turn the arrow. Balancing on the edge. Repulsive nuts. Turn on the light..........
- Amazing tapes. Radio signal. static separator. Jumping grains. Static rain..........
- Wrap film. Magic figurines. Influence of air humidity. Living doorknob. Sparkling clothes..........
- Charging at a distance. Rolling ring. Crack and clicks. Magic wand..........
- Everything can be charged. positive charge. The attraction of bodies static adhesive. Charged plastic. Ghost leg..........

"The use of home-made devices is one of the ways to activate the cognitive activity of students in the study of physics"

Esenzhulova A.D.

2016

Do you know how strong one person can be

Fedor Dostoevsky

annotation

This project is intended for physics teachers and students in grades 7-11. It provides an opportunity to get away from "chalk" physics, is aimed at attracting schoolchildren to the manufacture of devices and at identifying the creative abilities of children.

Relevance lies in the fact that the manufacture of devices leads not only to an increase in the level of knowledge, but also reveals the main direction of activity of students. When working on the device, we are moving away from "chalk" physics. A dry formula comes to life, an idea materializes, a complete and clear understanding arises. On the other hand, such work is a good example of socially useful work: well-made home-made devices can significantly replenish the equipment of a school office. Home-made devices have another constant value: their manufacture, on the one hand, develops practical skills and abilities in the teacher and students, and on the other hand, it testifies to creative work, to the methodological growth of the teacher.

The way out of a predicament is most often where the entrance was ...

Karel Capek

Problematic issues

• Is it worth it to manufacture home-made physics instruments when the industry produces them in sufficient quantity and high quality?
• How to replenish the physics classroom with equipment without material costs?
• What homemade devices should be made?

Make devices, installations in physics to demonstrate physical phenomena, explain the principle of operation of each device and demonstrate their work.

Hypothesis

The presence of home-made devices in the school physics classroom expands the possibilities for improving the educational experiment and improves the organization of scientific research.

1) study scientific and popular literature on the creation of home-made devices;

2) to make devices on specific topics that cause difficulty in understanding theoretical material in physics;

3) to make devices absent in the laboratory;

Diagnostic results

What do you like about studying physics ?

a) problem solving -19%;

b) demonstration of experiments - 21%;

c) reading a textbook at home - 4%;

d) teacher telling new material - 17%;

e) independent performance of experiments -36%;

f) the answer at the board is -3%.

What homework do you prefer to do?

a) reading a textbook -22%;

b) solving problems from a textbook -20%;

in) observation of physical phenomena -40%;

d) drafting tasks -7%;

e) manufacturing of simple devices, models -8%;

f) solving difficult problems - 3%.

What lesson are you interested in?

a) on control work - 3%;

b) in laboratory work - 60%;

c) at the lesson of problem solving - 8%;

d) at the lesson of learning new material - 22%;

e) don't know -7%.

Homemade device

DIY

Homemade device

Crusher

Homemade device

Sewing machine

Pupil 9 f Tishchenko A

Homemade device

Zhangabaev A 10 D class

Nuranov A 10 G class

1. Self-made physical installations have a greater didactic impact.

2. Home-made installations are created for specific conditions.

3. Home-made installations are a priori more reliable.

4. Homemade installations are much cheaper than state-owned appliances.

5. Homemade installations often determine the fate of a student.

I value one experience more than a thousand opinions

born only by imagination

M. Lomonosov

Conclusion

It's great if our project "charges" with creative optimism, makes someone believe in themselves. Indeed, this is its main goal: to present the complex as accessible, worth any effort and capable of giving a person an incomparable joy of comprehension, discovery. Perhaps our project will inspire someone to be creative. After all, creative vivacity is like a strong elastic spring, harboring the charge of a powerful blow. No wonder the wise aphorism says: “Only a beginner creator is omnipotent!”

Offer:

The assessment of the state and work of school physics classrooms should be carried out not by the dubious millions of rubles spent on dubious pseudo-equipment, but by the number of home-made installations, their coverage of the school physics course and school students.

Masters… Professionals

Those that in life were able to comprehend

The generosity of stone, the soul of metal

The freshness of the formula, the temper of the earth

Masters. Masters. Craftsmen

Understanding to the depths

Machine tool and heart mechanism

The stroke of the bow or the hum of the turbines

Prophetic hands stretching out

To the crossroads of the stellar worlds

Time moves by the masters and hopes for the masters!

... And they stand like fortresses,

In the rightness of your work

And they can't help it

And required

Robert Rozhdestvensky

Literature

1. N.M. Shakhmaev Physical experiment in high school.

2. L.I. Antsiferov. Homemade devices for a physical workshop.

3. N.M.Markosova. The study of ultrasound in the course of physics.

4. N.M. Zvereva. Activation of students' thinking in physics lessons.

5. S. Pavlovich. Instruments and models for inanimate nature.

6. I.Ya. Lanina. Not a single lesson.

7. S.A. Khoroshavin. Physical and technical modeling.

8. L.I. Antsiferov "Home-made devices for the Physical Workshop" Moscow Enlightenment 1985

9. A.I. Ukhanov "Home-made devices in physics" Saratov SSU 1978

DIY Tesla Coil. The resonant Tesla transformer is a very spectacular invention. Nikola Tesla was well aware of how spectacular the device was, and he constantly demonstrated it in public. Why do you think? That's right: to get additional funding.

You can feel like a great scientist and impress your friends by making your own mini-coil. You will need: a capacitor, a small light bulb, wire and a few other simple parts. However, remember that the Tesla resonant transformer produces a high voltage of high frequency - check the technical safety rules, otherwise the effect may turn into a defect.

Potato gun. An air gun that shoots potatoes? Easily! This is not a particularly dangerous project (unless you decide to make a giant and very powerful potato weapon). Potato Cannon is a great way to have fun for those who love engineering and petty mischief. The super weapon is pretty straightforward to make - you'll need an empty aerosol can and a couple of other parts that aren't hard to find.

High power toy machine. Remember children's toy machines - bright, with different functions, bang-bang, oh-oh-oh? The only thing that many boys lacked was to shoot a little further and a little harder. Well, we'll fix that.

Toy machines are made of rubber to be as safe as possible. Of course, the manufacturers made sure that the pressure in such pistols is minimal and cannot harm anyone. But some craftsmen still found a way to add power to children's weapons: you just need to get rid of the details that slow down the process. From what and how - says the experimenter from the video.

Drone with your own hands. Many people think of a drone solely as a large unmanned aerial vehicle used during military operations in the Middle East. This is a misconception: drones are becoming a daily occurrence, in most cases they are small, and it is not so difficult to make them at home.

Parts for a "homemade" drone are easy to obtain, and you don't have to be an engineer to assemble it entirely - although, of course, you will have to tinker. The average handmade drone consists of a small main body, a few additional parts (you can buy it or find it from other devices) and electronic equipment for remote control. Yes, a special pleasure is to equip a finished drone with a camera.

Theremin is the music of the magnetic field. This mysterious electric musical instrument is of interest not only (and not so much?) to musicians, but to mad scientists. An unusual device, invented by a Soviet inventor in 1920, you can assemble at home. Imagine: you just move your hands (of course, with the languid air of a scientist-musician), and the instrument makes “otherworldly” sounds!

Learning to masterfully control the theremin is not easy, but the result is worth it. Sensor, transistor, speaker, resistor, power supply, a couple more details, and you're good to go! Here's what it looks like.

If you do not feel confident in English, watch a Russian-language video on how to make a theremin from three radios.

Remote controlled robot. Well, who has not dreamed of a robot? Yes, and his own assembly! True, a fully autonomous robot will require serious titles and efforts, but a remote-controlled robot can be created from improvised materials. For example, the robot in the video is made of foam, wood, a small motor, and a battery. This "pet" under your leadership freely moves around the apartment, overcoming even uneven surfaces. With a little creativity, you can give it the look you want.

Plasma ball must have grabbed your attention. It turns out that you do not need to spend money on its acquisition, but you can gain confidence in yourself and do it yourself. Yes, at home it will be small, but still one touch to the surface will make it discharge with beautiful multi-colored "lightning bolts".

Main ingredients: induction coil, incandescent lamp and capacitor. Be sure to follow safety precautions - a spectacular device works under voltage.

solar powered radio- A great device for lovers of long hikes. Don't throw away your old radio: just attach a solar panel to it and you'll be independent of batteries and other power sources than the sun.

This is what a solar-powered radio looks like.

segway today incredibly popular, but considered an expensive toy. You can save a lot by spending only a few hundred instead of a thousand dollars, adding your own strength and time to them, and making a segway yourself. This is not an easy task, but it is quite real! It is interesting that today Segways are used not only as entertainment - in the United States they are used by postal workers, golfers and, which is especially striking, experienced Steadicam operators.

You can get acquainted with a detailed almost hour-long instruction - however, it is in English.

If you doubt that you understood everything correctly, below is the instruction in Russian - to get a general idea.

non-newtonian fluid allows you to do many fun experiments. It's completely safe and fun. A non-Newtonian fluid is a fluid whose viscosity depends on the nature of the external force. It can be made by mixing water with starch (one to two). Think it's easy? It wasn't there. The "foci" of a non-Newtonian fluid begin already in the process of its creation. Further more.

If you pick it up in a handful, it will look like polyurethane foam. If you start tossing, it will move like a living thing. Relax your hand and it will start to spread. Clench into a fist - it will become hard. It "dances" when you bring it to powerful speakers, but you can also dance on it if you stir enough to do so. In general, it is better to see once!

a- Davydov Roma Supervisor: physics teacher- Khovrich Lyubov Vladimirovna Novouspenka - 2008

Purpose: To make a device, a physics installation for demonstrating physical phenomena with your own hands. Explain the principle of operation of this device. Demonstrate the operation of this device.

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.

Objectives: 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.

EXPERIMENT 1: Forced vibrations. 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.

Forced vibrations

EXPERIMENT 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.

Jet propulsion

EXPERIMENT 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.

Sound waves.

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.

Coin in a bottle

Experiment 5: A floating balloon 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 easy 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?

floating ball

Experience 6: Body movement along the "dead loop" With the help of 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: 1. The ball is rolled down the rails from the highest point of the inclined rails, where it is held by an electromagnet powered by 24V. The ball stably describes the loop and flies out with some speed from the other end of the device2. The ball is rolled up from the lowest height when the ball only describes the loop without falling off its top point3. 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.

The movement of the body along the "dead loop"

Experiment 7: Hot air and cold air Stretch a balloon on 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

The air is hot and the air is cold

Experience 8: Stretching a solid body Taking a foam bar by the ends, we 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.

Stretching a rigid body

Test 9: Compressing a Solid Body Compressing a foam block along its major axis. To do this, they put it on a stand, cover it with a ruler from the top and apply pressure on it with a hand. A decrease in the distance between molecules and the appearance of repulsive forces between them are observed.

Compression of a rigid body

Experience 4: Double cone rolling up. This experiment serves to demonstrate an experience confirming that a freely moving object is always located in such a way that the center of gravity occupies the lowest possible position for it. Before the demonstration, the strips are placed at a certain angle. To do this, the double cone is placed with its ends into cutouts made in the upper edge of the planks. Then the cone is transferred down to the beginning of the planks and released. The cone will move up until its ends fall into the cutouts. In fact, the center of gravity of the cone, which lies on its axis, will be shifted downward, which is what we see.

Double cone, rolling up

The interest of students in the lesson with physical experience

Conclusion: It is interesting to observe the experience of 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.