For everyone and about everything. For everyone and about everything Experiment at home for children 10

And learn with them peace and wonders of physical phenomena? Then we invite you to our “experimental laboratory”, in which we will tell you how to create simple, but very interesting experiments for children.

Experiments with eggs

Egg with salt

The egg will sink to the bottom if you place it in a glass of plain water, but what happens if you add salt? The result is very interesting and can clearly show interesting facts about density.

You will need:

• Table salt
• Tumbler.

Instructions:

1. Fill half the glass with water.

2. Add a lot of salt to the glass (about 6 tablespoons).

3. We interfere.

4. Carefully lower the egg into the water and watch what happens.

Explanation

Salt water has a higher density than regular tap water. It is the salt that brings the egg to the surface. And if you add fresh water to the existing salt water, the egg will gradually sink to the bottom.

Egg in a bottle

Did you know that a boiled whole egg can easily be placed in a bottle?

You will need:

• A bottle with a neck diameter smaller than the diameter of an egg
• Hard boiled egg
• Matches
• Some paper
• Vegetable oil.

Instructions:

1. Lubricate the neck of the bottle with vegetable oil.

2. Now set fire to the paper (you can just use a few matches) and immediately throw it into the bottle.

3. Place an egg on the neck.

When the fire goes out, the egg will be inside the bottle.

Explanation

The fire provokes heating of the air in the bottle, which comes out. After the fire goes out, the air in the bottle will begin to cool and compress. Therefore, a low pressure is created in the bottle, and the external pressure forces the egg into the bottle.

Ball experiment

This experiment shows how rubber and orange peel interact with each other.

You will need:

• balloon
• Orange.

Instructions:

1. Inflate the balloon.

2. Peel the orange, but do not throw away the orange peel (zest).

3. Squeeze the orange zest over the ball until it pops.

Explanation.

Orange zest contains the substance limonene. It is capable of dissolving rubber, which is what happens to the ball.

Candle experiment

An interesting experiment showing ignition of a candle from a distance.

You will need:

• Regular candle
• Matches or lighter.

Instructions:

1. Light a candle.

2. After a few seconds, put it out.

3. Now bring the burning flame close to the smoke coming from the candle. The candle will start burning again.

Explanation

The smoke rising from an extinguished candle contains paraffin, which quickly ignites. The burning paraffin vapor reaches the wick, and the candle begins to burn again.

Soda with vinegar

A balloon that inflates itself is a very interesting sight.

You will need:

• Bottle
• Glass of vinegar
• 4 teaspoons soda
• Balloon.

Instructions:

1. Pour a glass of vinegar into the bottle.

2. Pour baking soda into the ball.

3. We put the ball on the neck of the bottle.

4. Slowly place the ball vertically while pouring the baking soda into the bottle with vinegar.

5. We watch the balloon inflate.

Explanation

If you add baking soda to vinegar, a process called soda slaking occurs. During this process, carbon dioxide is released, which inflates our balloon.

Invisible ink

Play secret agent with your child and create your own invisible ink.

You will need:

• Half a lemon
• Spoon
• Bowl
• Cotton swab
• White paper
• Lamp.

Instructions:

1. Squeeze some lemon juice into a bowl and add the same amount of water.

2. Dip a cotton swab into the mixture and write something on white paper.

3. Wait until the juice dries and becomes completely invisible.

4. When you are ready to read the secret message or show it to someone else, heat the paper by holding it close to a light bulb or fire.

Explanation

Lemon juice is an organic substance that oxidizes and turns brown when heated. Diluted lemon juice in water makes it hard to see on paper, and no one will know there is lemon juice until it warms up.

Other substances which work on the same principle:

• Orange juice
• Milk
• Onion juice
• Vinegar
• Wine.

How to make lava

You will need:

• Sunflower oil
• Juice or food coloring
• Transparent vessel (can be a glass)
• Any effervescent tablets.

Instructions:

1. First, pour the juice into a glass so that it fills approximately 70% of the container’s volume.

2. Fill the rest of the glass with sunflower oil.

3. Now wait until the juice separates from the sunflower oil.

4. We throw a tablet into a glass and observe an effect similar to lava. When the tablet dissolves, you can throw another one.

Explanation

Oil separates from water because it has a lower density. Dissolving in the juice, the tablet releases carbon dioxide, which captures parts of the juice and lifts it to the top. The gas leaves the glass completely when it reaches the top, causing the juice particles to fall back down.

The tablet fizzes due to the fact that it contains citric acid and soda (sodium bicarbonate). Both of these ingredients react with water to form sodium citrate and carbon dioxide gas.

Ice experiment

At first glance, you might think that the ice cube on top will eventually melt, which should cause the water to spill, but is this really so?

You will need:

• Cup
• Ice cubes.

Instructions:

1. Fill the glass with warm water to the very top.

2. Carefully lower the ice cubes.

3. Watch the water level carefully.

As the ice melts, the water level does not change at all.

Explanation

When water freezes to ice, it expands, increasing its volume (which is why even heating pipes can burst in winter). The water from melted ice takes up less space than the ice itself. Therefore, when the ice cube melts, the water level remains approximately the same.

How to make a parachute

Find out about air resistance, making a small parachute.

You will need:

• Plastic bag or other lightweight material
• Scissors
• A small load (possibly some kind of figurine).

Instructions:

1. Cut a large square from a plastic bag.

2. Now we cut the edges so that we get an octagon (eight identical sides).

3. Now we tie 8 pieces of thread to each corner.

4. Don't forget to make a small hole in the middle of the parachute.

5. Tie the other ends of the threads to a small weight.

6. We use a chair or find a high point to launch the parachute and check how it flies. Remember that the parachute should fly as slowly as possible.

Explanation

When the parachute is released, the weight pulls it down, but with the help of the lines, the parachute takes up a large area that resists the air, causing the weight to slowly descend. The larger the surface area of ​​the parachute, the more that surface resists falling, and the slower the parachute will descend.

A small hole in the middle of the parachute allows air to flow through it slowly rather than having the parachute tumble to one side.

How to make a tornado

Find out how to make a tornado in a bottle with this fun science experiment for kids. The items used in the experiment are easy to find in everyday life. Made home mini tornado much safer than the tornadoes shown on television in the American steppes.

Text: Katya Chekushina
Illustrations: Vlad Lesnikov

Experiment No. 1

French researcher Didier Desor from the University of Nancy published an interesting paper in 1994 entitled “Study of the social hierarchy of rats in water immersion experiments.”

Initially, six classic white laboratory rats participated in the experiment. When it was time to feed, they were placed in a glass box with a single exit at the top. This exit was a tunnel-staircase that descended to the bottom of an adjacent glass tank half filled with water. There was a feeder on the wall of the water tank, to which a rat, emerging from a tunnel at the bottom, could swim up and snatch a biscuit from there. However, in order to eat it, the animal had to return back to the hard surface of the stairs.

Very quickly, a clear hierarchy formed among the six participants in this experiment. Two rats became “exploiters”: they themselves did not swim, but took food from the three exploited swimmers. The sixth rat chose a self-sufficiency strategy: it dived for biscuits and successfully protected them from the racket. The most amazing thing was that no matter how many times the scientist repeated the experiment with different rats, in the end, exactly the same distribution of roles occurred! Even when a group included only exploiters, only slaves, or only independents, their community returned to the original hierarchy. If the group was increased, the result was even more impressive. Dr. Desor placed two hundred rats in a test cage. They fought all night. In the morning, three lifeless victims of a social cataclysm lay there, and a complex system of subordination had formed in the rat community. Food was brought to the “generals” by “lieutenants” who took it from the working swimmers. At the same time, in addition to the “autonomous”, a class of “beggars” was also formed: they did not swim or fight, but ate crumbs from the floor. Of course, Dr. Desor would not have been a real scientist if (to use a euphemism accepted in the scientific community) he had not donated his experimental subjects to science. After dissection, it turned out that all rats experienced increased levels of stress during the experiment. However, it was not the oppressed swimmers who suffered the most, but the exploiters!

At one time, this work made a lot of noise; behavioral scientists drew the darkest conclusions about the fate of society, the futility of revolutions, and the instinct for social injustice genetically embedded in us. The view, of course, is petty-bourgeois, but I think there is something in it.

Experiment No. 2

However, a rat's life is not always terrible. Take, for example, a recent experiment at the Polytechnic University of Marche, Italy, in which no animals were harmed. Quite the contrary. During the experiments, the rats consumed strawberry puree at the rate of 40 mg per kilo of body weight along with their main food for ten days. After this they were given alcohol. The control group at this moment drank alcohol without any strawberry ceremonies. True, at the end of the experiment, all the happy participants suffered a hangover, aggravated by the study of the condition of the mucous membrane of their stomachs, which the researchers started. It turned out that rats who ate the berries were less likely to develop ulcers. “The positive effect of strawberries lies not only in the antioxidants they contain,” says Dr. Sarah Tulipani, “but also in the fact that they stimulate the production of natural enzymes in the body.” Who would argue! We also believe that when experimenting with alcohol, many things seem very positive. And strawberries are definitely one of them.

Experiment No. 3
Universe-25

One day, Dr. John B. Calhoun decided to create a mouse paradise. He took a tank two by two meters, installed ceilings in it, laid a system of tunnels with individual compartments and drinking bowls, and at the beginning of 1972, he released four pairs of healthy, genetically flawless mice into this paradise. The tank was always +20 oC, every month it was cleaned and filled with food and nesting material. Universe 25, as Calhoun called the tank, was in a golden age. A hundred days later, realizing their happiness, the rodents began to multiply wildly. The population doubled every 55 days, and no expulsion was expected for the Fall. However, even at the moment of its creation, the “universe” was doomed. After all, number 25 was not chosen by chance. This was already the 25th experiment on rats and mice, and each time heaven turned into hell. The mice, which by the 315th day had multiplied to 600 individuals, already categorically did not have enough space. Society began to rapidly collapse. Curious classes were formed: “nonconformists”, who huddled in the center and regularly attacked nest owners, “beautiful” - males who were not interested in reproduction and looked after themselves exclusively, and, finally, the “middle class”, who tried to maintain the familiar at any cost. way of life Violence, sin and even cannibalism flourished in the tank. Eventually, 90% of the females of reproductive age left the population and settled in isolated nests at the top of the tank. On the 560th day, Universe-25 was effectively finished. The population peaked at 2,200 individuals, the birth rate fell, and rare pregnancies ended in the killing of the cubs. The increased mortality did not save paradise: the last eight mice died one after another, never returning to their usual roles or trying to have babies! In his work “Population Density and Social Pathologies,” Calhoun, along with “Universe 25,” buried all of humanity: “Even before we run out of resources, people will suffocate in their cities!” I would like to say: can’t wait! But…

Experiment No. 4

You may have heard about the classic experiment from the 1950s, in which psychologists Olds and Miller accidentally discovered a “pure happiness” zone in the brains of rats. Let's not exaggerate the scientists' good intentions: initially they planned to cause pain to the rats. However, by placing the electrodes almost in the very center of the brain, scientists unexpectedly discovered that the rat pressed the lever again and again, completing the electrical circuit. Further experiments showed that some individuals are ready to press the lever almost continuously, 2000 times per hour, forgetting about sleep and food. Neither sexually mature females nor physical pain could stop the male on his way to the treasured “pleasure button.” The limbic areas of the brain that were stimulated in rats during this experiment were formed at the very dawn of evolution. All mammals, including humans, have them, although it is still not very clear what they are responsible for. So, recently the records of other scientists were made public who, not entirely legally, conducted similar experiments on homosexuals and patients in psychiatric hospitals. The essence of “pure happiness” turned out to be extremely simple: people described this feeling as... a delightful orgasm.

Experiment No. 5
Sex, drugs, loud music

We're at a loss as to what possessed students at the University of Bari in Italy to do such a thing, but in September 2008, a report appeared in the medical literature about "the effects of ecstasy and loud music on the sexual behavior of white rats." Subjects were given a moderate dose of the drug, then changes in their sexual behavior were recorded. There was none. Scientists concluded that under the influence of methylenediohimethamphetamine, adult rats lose interest in females. But, if you turn on rhythmic music loudly an hour after taking the drug, sexual contacts resume. Whether this experience proved the harm of ecstasy or the benefits of loud music - the medical community has not yet decided.

Experiment No. 6

In 2007, Richard Hanson and Parvin Hakimi of Case Western Reserve University in Ohio modified the mouse genome and bred about 500 supermice that were several times more resilient than their relatives. Not only could the mouse superheroes run without rest for six hours, while the average mouse runs out of steam after half an hour, but they also lived longer, maintained reproductive abilities into old age, and also consumed 60% more food than the control group, while while remaining leaner and more athletic. A remarkable experiment not only proved that by modifying just one gene it is possible to significantly speed up the metabolism of a living being, but also that nothing like this will happen to people in the near future. The special commission found it unethical to even think about it. So don't even think about it!

Experiment No. 7
Morphine and entertainment

In the late 1970s, Canadian researcher Bruce K. Alexander came to the conclusion that rats do not have enough entertainment (in fact, it seems that all the scientists in our selection came to this conclusion and the rats had absolutely nothing to do with it). Dr. Alexander was not too original: he decided to study the formation of drug addiction. A Canadian scientist volunteered to prove that the persistent addiction of rats to drugs, which has been proven by numerous experiments, is caused by the fact that the experimental animals were locked in cramped cages and had no choice but to entertain themselves with injections. To confirm his theory, Dr. Alexander built a kind of rat amusement park - a spacious dwelling in which there were tunnels, squirrel wheels, balls for playing, cozy nests and an abundance of food. 20 rats of different sexes were placed there. The control group was crowded into classic cages. Both were given two drinking bowls, one of which contained ordinary water, and the other a sweetened morphine solution (rats have a sweet tooth and at first refuse to drink the narcotic solution because of its bitterness). As a result, Alexander's theory was completely confirmed. The inhabitants of the cages very quickly became addicted to morphine, but the happy inhabitants of the park completely ignored the drug. True, some of the park rats tried water with morphine several times, as if wanting to make sure of the effect obtained (as a rule, these were females), but none of them showed signs of regular dependence. As befits a creator, Dr. Alexander could not deny himself the pleasure of playing with the destinies of his charges and at a certain stage swapped some of the park and cage rats. It is quite logical that rodents, suddenly and inexplicably finding themselves in cramped living conditions, immediately became addicted to morphine. But those who were moved to the park of cages turned out to be more cunning. They continued to use the drug, only less regularly - just enough to maintain euphoria, but to be able to perform their basic social functions.

In fact, Dr. Alexander’s experiments radically shook the prevailing theory in medical circles about the chemical origin of opioid addiction, which the addict is unable to control. But the scientific community pretended that nothing had happened, and the experiment was hushed up. But we don’t pretend to be scientific, we can do it!

Experiment No. 8

Yes, the rats managed to experience something that you and I had only dreamed of - mating in zero gravity! The case, however, was completed in a hurry, since the experiment was very limited in time: it took place within the framework of the flights of the special experimental apparatus “Photon”. Transporting rat cages to the ISS, where animals could mate with feeling, sense and arrangement, is too expensive. A rat's life support system in zero gravity takes up a lot of space, and this is the most important resource on an orbital station. By the way, you can be proud: in the matter of sex in zero gravity, we are ahead of the rest, since it was our scientists who carried out this experiment with rats on the Photon. Alas, its result can hardly be called successful. By all indications, mating took place, but the females did not become pregnant. However, if we ignore rats, in most cases this is not a minus, but very much a plus.

Experiment No. 9
Gluttony

Perhaps, scientific rats managed to participate in all the sins of humanity (with the help of scientists, of course). Such a primitive sin as gluttony was also not spared. For its full implementation, the brothers Louis and Theodore Zucker bred special genetically modified rats that proudly bore the names of their creators. In fact, the whole purpose of Zucker rats was to consume food throughout their lives. They had an increased sense of hunger and could weigh twice as much as their unmodified ancestors. The rats paid for their sins in this life: they had high cholesterol levels in the blood and a whole bunch of diseases.

Experiment No. 10
Experiment on the experimenter

The logical conclusion of this series of merciless experiments on animals, we believe, was an experiment on humans with rats, which was conducted by psychologist Dr. Rosenthal at Harvard in 1963. He suggested that his students train rats to navigate a maze. At the same time, half of the students were told that they had rats of a special intellectual breed that learned very quickly. The other half of the students worked with “ordinary rats.” After a week of training, teachers of “intelligent” rodents received significantly higher results than students who trained “ordinary” rodents.

As you probably guessed, the rats were exactly the same. Well, firstly, this proves that you should never trust the first professor you meet and agree to dubious experiments: it’s not a fact that you won’t end up being their object. Secondly, believing and agreeing - in some cases means getting an inflated result absolutely from scratch!

Friends, good afternoon! Agree, how interesting it is sometimes to surprise our little ones! They have such a funny reaction to . It shows that they are ready to learn, ready to absorb new material. The whole world opens up at this moment before them and for them! And we, parents, act as real wizards with a hat from which we “pull out” something incredibly interesting, new and very important!

What will we get out of the “magic” hat today? We have 25 experimental experiments there for children and adults. They will be prepared for kids of different ages in order to interest them and involve them in the process. Some can be carried out without any preparation, using handy tools that each of us has at home. For others, we will buy some materials so that everything goes smoothly. Well? I wish us all good luck and move forward!

Today will be a real holiday! And in our program:

Ice soap bubbles

What do you think will happen if simple bubbles that are tiny in 4 years loves to inflate them, run after them and burst them, inflate them in the cold. Or rather, straight into a snowdrift.

I'll give you a hint:

• they will burst immediately!
• take off and fly away!
• will freeze!

Whatever you choose, I can tell you right away, it will surprise you! Can you imagine what will happen to the little one?!

But in slow motion it’s just a fairy tale!

I'm complicating the question. Is it possible to repeat the experiment in the summer in order to get a similar option?

Choose answers:

• Yes. But you need ice from the refrigerator.

You know, although I really want to tell you everything, this is exactly what I won’t do! Let there be at least one surprise for you too!

Paper vs water

The real one is waiting for us experiment. Is it really possible for paper to defeat water? This is a challenge for everyone who plays Rock-Paper-Scissors!

What we need:

• Sheet of paper;
• Water in a glass.

Cover the glass. It would be good if its edges were a little damp, then the paper would stick. Carefully turn the glass over... No water leaks!

Let's inflate balloons without breathing?

We have already carried out chemical children's experiments. Remember, the very first room for very little babies was a room with vinegar and soda. So, let's continue! And we use the energy, or rather, the air, that is released during the reaction for peaceful and inflatable purposes.

Ingredients:

• Soda;
• Plastic bottle;
• Vinegar;
• Ball.

Pour soda into the bottle and fill 1/3 with vinegar. Shake lightly and quickly pull the ball onto the neck. When it is inflated, bandage it and remove it from the bottle.

Such a small experience can show even in kindergarten.

Rain from a cloud

We need:

• Jar of water;
• Shaving foam;
• Food coloring (any color, several colors are possible).

We make a cloud of foam. A big and beautiful cloud! Entrust this to the best cloud maker, your child. 5 years. He will definitely make her real!

author of the photo

All that remains is to distribute the dye over the cloud, and... drip-drip! It's raining!

Rainbow

Maybe, physics the children are still unknown. But after they make Rainbow, they will definitely love this science!

• Deep transparent container with water;
• Mirror;
• Flashlight;
• Paper.

Place a mirror at the bottom of the container. We shine a flashlight on the mirror at a slight angle. All that remains is to catch the Rainbow on paper.

Even easier is to use a disk and a flashlight.

Crystals

There is a similar, only already finished game. But our experience interesting the fact that we ourselves, from the very beginning, will grow crystals from salt in water. To do this, take a thread or wire. And let's keep it for several days in such salty water, where the salt can no longer dissolve, but accumulates in a layer on the wire.

Can be grown from sugar

Lava jar

If you add oil to a jar of water, it will all accumulate on top. It can be tinted with food coloring. But in order for the bright oil to sink to the bottom, you need to pour salt on top of it. Then the oil will settle. But not for long. The salt will gradually dissolve and release beautiful droplets of oil. The colored oil rises gradually, as if a mysterious volcano is bubbling inside the jar.

Volcanic eruption

For toddlers 7 years It will be very interesting to blow up, demolish, destroy something. In a word, this is a real element of nature for them. and therefore we create a real, exploding volcano!

We sculpt from plasticine or make a “mountain” from cardboard. We place a jar inside it. Yes, so that its neck fits the “crater”. Fill the jar with soda, dye, warm water and... vinegar. And everything will begin to “explode, lava will rush up and flood everything around!

A hole in the bag is not a problem

This is what convinces book of scientific experiments for children and adults Dmitry Mokhov "Simple Science". And we can check this statement ourselves! First, fill the bag with water. and then we'll pierce it. But we won’t remove what we pierced with (a pencil, a toothpick or a pin). How much water will we leak? Let's check!

Water that doesn't spill

Only such water still needs to be produced.

Take water, paint and starch (as much as water) and mix. The end result is just plain water. You just can't spill it!

"Slippery" egg

In order for the egg to actually fit into the neck of the bottle, you need to set fire to the piece of paper and throw it into the bottle. Cover the hole with an egg. When the fire goes out, the egg will slip inside.

Snow in summer

This trick is especially interesting to repeat in the warm season. Remove the contents of the diapers and wet them with water. All! The snow is ready! Nowadays such snow is easy to find in children's toys in stores. Ask the seller for artificial snow. And no need to ruin diapers.

Moving snakes

To make a moving figure we will need:

• Sand;
• Alcohol;
• Sugar;
• Soda;
• Fire.

Pour alcohol onto a pile of sand and let it soak. Then pour sugar and baking soda on top and set it on fire! Oh, what a funny this experiment! Children and adults will love what the animated snake gets up to!

Of course, this is for older children. And it looks pretty scary!

Battery train

The copper wire, which we twist into an even spiral, will become our tunnel. How? Let's connect its edges, forming a round tunnel. But before that, we “launch” the battery inside, only attaching neodymium magnets to its edges. And consider that you have invented a perpetual motion machine! The locomotive moved on its own.

Candle swing

To light both ends of the candle, you need to clear the wax from the bottom down to the wick. Heat a needle over the fire and pierce the candle in the middle with it. Place the candle on 2 glasses so that it rests on the needle. Burn the edges and shake slightly. Then the candle itself will swing.

Elephant tooth paste

The elephant needs everything big and a lot. Let's do it! Dissolve potassium permanganate in water. Add liquid soap. The last ingredient, hydrogen peroxide, turns our mixture into a giant elephant paste!

Let's drink a candle

For greater effect, color the water in a bright color. Place a candle in the middle of the saucer. We set it on fire and cover it with a transparent container. Pour water into a saucer. At first the water will be around the container, but then it will all be saturated inside, towards the candle.
Oxygen is burned, the pressure inside the glass decreases and

A real chameleon

What will help our chameleon change color? Cunning! Instruct your little one 6 years Decorate a plastic plate in different colors. And cut out the chameleon figure yourself on another plate, similar in shape and size. All that remains is to loosely connect both plates in the middle so that the top one, with the cut out figure, can rotate. Then the color of the animal will always change.

Light up the rainbow

Place Skittles in a circle on a plate. Pour water inside the plate. Just wait a little and we get a rainbow!

Smoke rings

Cut off the bottom of the plastic bottle. And pull the edge of the cut balloon to get a membrane, as in the photo. Light an incense stick and place it in the bottle. Close the lid. When there is continuous smoke in the jar, unscrew the lid and tap on the membrane. Smoke will come out in rings.

Multicolored liquid

To make everything look more impressive, paint the liquid in different colors. Make 2-3 batches of multi-colored water. Pour water of the same color into the bottom of the jar. Then carefully pour vegetable oil along the wall from different sides. Pour water mixed with alcohol over it.

Egg without shell

Place a raw egg in vinegar for at least a day, some say for a week. And the trick is ready! An egg without a hard shell.
The egg shell contains calcium in abundance. Vinegar reacts actively with calcium and gradually dissolves it. As a result, the egg is covered with a film, but completely without a shell. It feels like an elastic ball.
And the egg will be larger than its original size, as it will absorb some of the vinegar.

Dancing men

It's time to get rowdy! Mix 2 parts starch with one part water. Place a bowl of starchy liquid on the speakers and turn up the bass!

Decorating the ice

We decorate ice figures of different shapes using food paint mixed with water and salt. The salt eats away at the ice and seeps deep, creating interesting passages. Great idea for color therapy.

Launching paper rockets

We empty the tea bags of tea by cutting off the top. Let's set it on fire! Warm air lifts the bag!

There are so many experiences that you will definitely find something to do with your children, just choose! And don’t forget to come back again for a new article, which you’ll hear about if you subscribe! Invite your friends to visit us too! That's all for today! Bye!

Hundreds of thousands of physical experiments have been carried out over the thousand-year history of science. It is difficult to select several “best.” A survey was conducted among physicists in the USA and Western Europe. Researchers Robert Creese and Stoney Book asked them to name the most beautiful physics experiments in history. Igor Sokalsky, a researcher at the Laboratory of High Energy Neutrino Astrophysics, Candidate of Physical and Mathematical Sciences, spoke about the experiments that were included in the top ten according to the results of a selective survey by Kriz and Buk.

1. Experiment of Eratosthenes of Cyrene

One of the oldest known physical experiments, as a result of which the radius of the Earth was measured, was carried out in the 3rd century BC by the librarian of the famous Library of Alexandria, Erastothenes of Cyrene. The experimental design is simple. At noon, on the day of the summer solstice, in the city of Siena (now Aswan), the Sun was at its zenith and objects did not cast shadows. On the same day and at the same time, in the city of Alexandria, located 800 kilometers from Siena, the Sun deviated from the zenith by approximately 7°. This is about 1/50 of a full circle (360°), which means that the circumference of the Earth is 40,000 kilometers and the radius is 6,300 kilometers. It seems almost incredible that the radius of the Earth measured by such a simple method turned out to be only 5% less than the value obtained by the most accurate modern methods, reports the Chemistry and Life website.

2. Galileo Galilei's experiment

In the 17th century, the dominant point of view was Aristotle, who taught that the speed at which a body falls depends on its mass. The heavier the body, the faster it falls. Observations that each of us can make in everyday life would seem to confirm this. Try letting go of a light toothpick and a heavy stone at the same time. The stone will touch the ground faster. Such observations led Aristotle to the conclusion about the fundamental property of the force with which the Earth attracts other bodies. In fact, the speed of falling is affected not only by the force of gravity, but also by the force of air resistance. The ratio of these forces for light objects and for heavy ones is different, which leads to the observed effect.

The Italian Galileo Galilei doubted the correctness of Aristotle's conclusions and found a way to test them. To do this, he dropped a cannonball and a much lighter musket bullet from the Leaning Tower of Pisa at the same moment. Both bodies had approximately the same streamlined shape, therefore, for both the core and the bullet, the air resistance forces were negligible compared to the forces of gravity. Galileo found that both objects reach the ground at the same moment, that is, the speed of their fall is the same.

The results obtained by Galileo are a consequence of the law of universal gravitation and the law according to which the acceleration experienced by a body is directly proportional to the force acting on it and inversely proportional to its mass.

3. Another Galileo Galilei experiment

Galileo measured the distance that balls rolling on an inclined board covered in equal intervals of time, measured by the author of the experiment using a water clock. The scientist found that if the time was doubled, the balls would roll four times further. This quadratic relationship meant that the balls moved at an accelerated rate under the influence of gravity, which contradicted Aristotle's assertion, which had been accepted for 2000 years, that bodies on which a force acts move at a constant speed, whereas if no force is applied to the body, then it is at rest. The results of this experiment by Galileo, like the results of his experiment with the Leaning Tower of Pisa, later served as the basis for the formulation of the laws of classical mechanics.

4. Henry Cavendish's experiment

After Isaac Newton formulated the law of universal gravitation: the force of attraction between two bodies with masses Mit, separated from each other by a distance r, is equal to F=γ (mM/r2), it remained to determine the value of the gravitational constant γ - For this it was necessary to measure the force attraction between two bodies with known masses. This is not so easy to do, because the force of attraction is very small. We feel the force of gravity of the Earth. But it is impossible to feel the attraction of even a very large mountain nearby, since it is very weak.

A very subtle and sensitive method was needed. It was invented and used in 1798 by Newton's compatriot Henry Cavendish. He used a torsion scale - a rocker with two balls suspended on a very thin cord. Cavendish measured the displacement of the rocker arm (rotation) as other balls of greater mass approached the scales. To increase sensitivity, the displacement was determined by light spots reflected from mirrors mounted on the rocker balls. As a result of this experiment, Cavendish was able to quite accurately determine the value of the gravitational constant and calculate the mass of the Earth for the first time.

5. Jean Bernard Foucault's experiment

French physicist Jean Bernard Leon Foucault experimentally proved the rotation of the Earth around its axis in 1851 using a 67-meter pendulum suspended from the top of the dome of the Parisian Pantheon. The swing plane of the pendulum remains unchanged in relation to the stars. An observer located on the Earth and rotating with it sees that the plane of rotation is slowly turning in the direction opposite to the direction of rotation of the Earth.

6. Isaac Newton's experiment

In 1672, Isaac Newton performed a simple experiment that is described in all school textbooks. Having closed the shutters, he made a small hole in them through which a ray of sunlight passed. A prism was placed in the path of the beam, and a screen was placed behind the prism. On the screen, Newton observed a “rainbow”: a white ray of sunlight, passing through a prism, turned into several colored rays - from violet to red. This phenomenon is called light dispersion.

Sir Isaac was not the first to observe this phenomenon. Already at the beginning of our era, it was known that large single crystals of natural origin have the property of decomposing light into colors. The first studies of light dispersion in experiments with a glass triangular prism, even before Newton, were carried out by the Englishman Hariot and the Czech naturalist Marzi.

However, before Newton, such observations were not subjected to serious analysis, and the conclusions drawn on their basis were not cross-checked by additional experiments. Both Hariot and Marzi remained followers of Aristotle, who argued that differences in color were determined by differences in the amount of darkness “mixed” with white light. Violet color, according to Aristotle, occurs when darkness is added to the greatest amount of light, and red - when darkness is added to the least amount. Newton carried out additional experiments with crossed prisms, when light passed through one prism then passes through another. Based on the totality of his experiments, he concluded that “no color arises from white and black mixed together, except the intermediate dark ones.”

the amount of light does not change the appearance of the color.” He showed that white light should be considered as a compound. The main colors are from purple to red.

This Newton experiment serves as a remarkable example of how different people, observing the same phenomenon, interpret it differently, and only those who question their interpretation and conduct additional experiments come to the correct conclusions.

7. Thomas Young's experiment

Until the beginning of the 19th century, ideas about the corpuscular nature of light prevailed. Light was considered to consist of individual particles - corpuscles. Although the phenomena of diffraction and interference of light were observed by Newton (“Newton’s rings”), the generally accepted point of view remained corpuscular.

Looking at the waves on the surface of the water from two thrown stones, you can see how, overlapping each other, the waves can interfere, that is, cancel out or mutually reinforce each other. Based on this, the English physicist and physician Thomas Young conducted experiments in 1801 with a beam of light that passed through two holes in an opaque screen, thus forming two independent light sources, similar to two stones thrown into water. As a result, he observed an interference pattern consisting of alternating dark and white fringes, which could not be formed if light consisted of corpuscles. The dark stripes corresponded to areas where light waves from the two slits cancel each other out. Light stripes appeared where light waves mutually reinforced each other. Thus, the wave nature of light was proven.

8. Klaus Jonsson's experiment

German physicist Klaus Jonsson conducted an experiment in 1961 similar to Thomas Young's experiment on the interference of light. The difference was that instead of rays of light, Jonsson used beams of electrons. He obtained an interference pattern similar to what Young observed for light waves. This confirmed the correctness of the provisions of quantum mechanics about the mixed corpuscular-wave nature of elementary particles.

9. Robert Millikan's experiment

The idea that the electric charge of any body is discrete (that is, consists of a larger or smaller set of elementary charges that are no longer subject to fragmentation) arose at the beginning of the 19th century and was supported by such famous physicists as M. Faraday and G. Helmholtz. The term “electron” was introduced into the theory, denoting a certain particle - the carrier of an elementary electric charge. This term, however, was purely formal at that time, since neither the particle itself nor the elementary electric charge associated with it had been discovered experimentally. In 1895, K. Roentgen, during experiments with a discharge tube, discovered that its anode, under the influence of rays flying from the cathode, was capable of emitting its own X-rays, or Roentgen rays. In the same year, French physicist J. Perrin experimentally proved that cathode rays are a stream of negatively charged particles. But, despite the colossal experimental material, the electron remained a hypothetical particle, since there was not a single experiment in which individual electrons would participate.

American physicist Robert Millikan developed a method that has become a classic example of an elegant physics experiment. Millikan managed to isolate several charged droplets of water in space between the plates of a capacitor. By illuminating with X-rays, it was possible to slightly ionize the air between the plates and change the charge of the droplets. When the field between the plates was turned on, the droplet slowly moved upward under the influence of electrical attraction. When the field was turned off, it fell under the influence of gravity. By turning the field on and off, it was possible to study each of the droplets suspended between the plates for 45 seconds, after which they evaporated. By 1909, it was possible to determine that the charge of any droplet was always an integer multiple of the fundamental value e (electron charge). This was convincing evidence that electrons were particles with the same charge and mass. By replacing droplets of water with droplets of oil, Millikan was able to increase the duration of observations to 4.5 hours and in 1913, eliminating one by one possible sources of error, he published the first measured value of the electron charge: e = (4.774 ± 0.009)x 10-10 electrostatic units .

10. Ernst Rutherford's experiment

By the beginning of the 20th century, it became clear that atoms consist of negatively charged electrons and some kind of positive charge, due to which the atom remains generally neutral. However, there were too many assumptions about what this “positive-negative” system looks like, while there was clearly a lack of experimental data that would make it possible to make a choice in favor of one or another model. Most physicists accepted J. J. Thomson's model: the atom as a uniformly charged positive ball with a diameter of approximately 108 cm with negative electrons floating inside.

In 1909, Ernst Rutherford (assisted by Hans Geiger and Ernst Marsden) conducted an experiment to understand the actual structure of the atom. In this experiment, heavy positively charged alpha particles moving at a speed of 20 km/s passed through thin gold foil and were scattered on gold atoms, deviating from the original direction of motion. To determine the degree of deviation, Geiger and Marsden had to use a microscope to observe the flashes on the scintillator plate that occurred where the alpha particle hit the plate. Over the course of two years, about a million flares were counted and it was proven that approximately one particle in 8000, as a result of scattering, changes its direction of motion by more than 90° (that is, turns back). This could not possibly happen in Thomson’s “loose” atom. The results clearly supported the so-called planetary model of the atom - a massive tiny nucleus measuring about 10-13 cm and electrons rotating around this nucleus at a distance of about 10-8 cm.

Modern physical experiments are much more complex than experiments of the past. In some, devices are placed over areas of tens of thousands of square kilometers, in others they fill a volume of the order of a cubic kilometer. And still others will soon be carried out on other planets.

We bring to your attention 10 amazing magic experiments, or science shows, that you can do with your own hands at home.
Whether it's your child's birthday party, the weekend, or the holidays, make the most of your time and become the center of attention of many eyes! 🙂

An experienced organizer of scientific shows helped us in preparing this post - Professor Nicolas. He explained the principles that are inherent in this or that focus.

1 - Lava lamp

1. Surely many of you have seen a lamp with a liquid inside that imitates hot lava. Looks magical.

2. Water is poured into sunflower oil and food coloring (red or blue) is added.

3. After this, add effervescent aspirin to the vessel and observe an amazing effect.

4. During the reaction, the colored water rises and falls through the oil without mixing with it. And if you turn off the light and turn on the flashlight, the “real magic” will begin.

: “Water and oil have different densities, and they also have the property of not mixing, no matter how much we shake the bottle. When we add effervescent tablets inside the bottle, they dissolve in water and begin to release carbon dioxide and set the liquid in motion.”

Do you want to put on a real science show? More experiments can be found in the book.

2 - Soda experience

5. Surely there are several cans of soda at home or in a nearby store for the holiday. Before you drink them, ask the kids the question: “What happens if you immerse soda cans in water?”
Will they drown? Will they float? Depends on the soda.
Invite the children to guess in advance what will happen to a particular jar and conduct an experiment.

6. Take the jars and carefully lower them into the water.

7. It turns out that despite the same volume, they have different weights. This is why some banks sink and others don't.

Professor Nicolas's comment: “All our cans have the same volume, but the mass of each can is different, which means that the density is different. What is density? This is the mass divided by the volume. Since the volume of all cans is the same, the density will be higher for the one whose mass is greater.
Whether a jar will float or sink in a container depends on the ratio of its density to the density of water. If the density of the jar is less, then it will be on the surface, otherwise the jar will sink to the bottom.
But what makes a can of regular cola denser (heavier) than a can of diet drink?
It's all about the sugar! Unlike regular cola, where granulated sugar is used as a sweetener, a special sweetener is added to diet cola, which weighs much less. So how much sugar is in a regular can of soda? The difference in mass between regular soda and its diet counterpart will give us the answer!”

3 - Paper cover

Ask those present: “What happens if you turn a glass of water over?” Of course it will pour out! What if you press the paper against the glass and turn it over? Will the paper fall and water will still spill on the floor? Let's check it out.

10. Carefully cut out the paper.

11. Place on top of the glass.

12. And carefully turn the glass over. The paper stuck to the glass as if magnetized, and the water did not spill out. Miracles!

Professor Nicolas's comment: “Although this is not so obvious, in fact we are in a real ocean, only in this ocean there is not water, but air, which presses on all objects, including you and me, we are just so used to it to this pressure that we don’t notice it at all. When we cover a glass of water with a piece of paper and turn it over, water presses on the sheet on one side, and air on the other side (from the very bottom)! The air pressure turned out to be greater than the water pressure in the glass, so the leaf does not fall.”

4 - Soap Volcano

How to make a small volcano erupt at home?

14. You will need baking soda, vinegar, some dishwashing chemicals and cardboard.

16. Dilute vinegar in water, add washing liquid and tint everything with iodine.

17. We wrap everything in dark cardboard - this will be the “body” of the volcano. A pinch of soda falls into the glass and the volcano begins to erupt.

Professor Nicolas's comment: “As a result of the interaction of vinegar with soda, a real chemical reaction occurs with the release of carbon dioxide. And liquid soap and dye, interacting with carbon dioxide, form colored soap foam - and that’s the eruption.”

5 - Spark plug pump

Can a candle change the laws of gravity and lift water up?

19. Place the candle on the saucer and light it.

20. Pour the colored water onto a saucer.

21. Cover the candle with a glass. After some time, the water will be drawn inside the glass, contrary to the laws of gravity.

Professor Nicolas's comment: “What does the pump do? Changes the pressure: increases (then water or air begins to “escape”) or, conversely, decreases (then gas or liquid begins to “arrive”). When we covered the burning candle with a glass, the candle went out, the air inside the glass cooled, and therefore the pressure decreased, so the water from the bowl began to be sucked in.”

Games and experiments with water and fire are in the book "Professor Nicolas' Experiments".

6 - Water in a sieve

We continue to study the magical properties of water and surrounding objects. Ask someone present to pull the bandage and pour water through it. As we can see, it passes through the holes in the bandage without any difficulty.
Bet with those around you that you can make sure that water does not pass through the bandage without any additional techniques.

22. Cut a piece of bandage.

23. Wrap a bandage around a glass or champagne flute.

24. Turn the glass over - the water doesn’t spill out!

Professor Nicolas's comment: “Thanks to this property of water, surface tension, water molecules want to be together all the time and are not so easy to separate (they are such wonderful girlfriends!). And if the size of the holes is small (as in our case), then the film does not tear even under the weight of water!”

7 - Diving bell

And to secure the honorary title of Water Mage and Lord of the Elements for you, promise that you can deliver paper to the bottom of any ocean (or bathtub or even basin) without getting it wet.

25. Have those present write their names on a piece of paper.

26. Fold the piece of paper and put it in the glass so that it rests against its walls and does not slide down. We immerse the leaf in an inverted glass to the bottom of the tank.

27. The paper remains dry - water cannot reach it! After you pull out the leaf, let the audience make sure that it is really dry.