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 experiments will help you see extraordinary phenomena light and sound, electricity and magnetism Everything necessary for the experiments is easy to find at home, and the experiments themselves simple and safe.
Your eyes are burning, your hands are itching!
Go ahead, explorers!
Robert Wood - a genius of experimentation.........
- Up or down? Rotating chain. Fingers of salt......... - The Moon and diffraction. What color is the fog? Newton's rings......... - A 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. Rotating spiral......... - Condensation in a jar. Where is the water vapor? Water engine........ - Popping egg. An overturned glass. Swirl in a cup. Heavy newspaper.........
- IO-IO toy. Salt pendulum. Paper dancers. Electric dance.........
- The mystery of ice cream. Which water will freeze faster? It's frosty, but the ice is melting! .......... - Let's make a rainbow. A mirror that doesn't confuse. Microscope made from a drop of water.........
- The snow creaks. What will happen to the icicles? Snow flowers......... - Interaction of sinking objects. Ball is touchable.........
- Who is faster? Reactive balloon. Air carousel......... - Bubbles from a funnel. Green hedgehog. Without opening the bottles......... - Spark plug motor. Bump or hole? A moving rocket. Divergent rings.........
- Multi-colored balls. Sea resident. Balancing egg.........
- Electric motor in 10 seconds. Gramophone..........
- Boil, cool......... - Waltzing dolls. Flame on paper. Robinson's feather.........
- Faraday experiment. 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
- Jumping grasshopper. Jumping ring. Elastic coins..........
Friction
- Reel-crawler..........
- Drowned thimble. Obedient ball. We measure friction. Funny monkey. Vortex rings.........
- Rolling and sliding. Rest friction. The acrobat is doing a cartwheel. Brake in the egg.........
Inertia and inertia
- Take out the coin. Experiments with bricks. Wardrobe experience. Experience with matches. Inertia of the coin. Hammer experience. Circus experience with a jar. Experiment with a ball.........
- Experiments with checkers. Domino experience. Experiment with an egg. Ball in a glass. Mysterious skating rink.........
- Experiments with coins. Water hammer. Outsmarting inertia.........
- Experience with boxes. Experience with checkers. Coin experience. Catapult. Inertia of an apple.........
- Experiments with rotational inertia. Experiment with a ball.........
Mechanics. Laws of mechanics
- Newton's first law. Newton's third law. Action and reaction. Law of conservation of momentum. Quantity of movement.........
Jet propulsion
- Jet shower. Experiments with jet spinners: air spinner, jet balloon, ethereal spinner, Segner wheel..........
- Balloon rocket. Multistage rocket. Pulse ship. Jet boat.........
Free fall
-Which is faster.........
Circular movement
- Centrifugal force. Easier on turns. Experience with the ring.........
Rotation
- Gyroscopic toys. Clark's top. Greig's top. Lopatin's flying top. Gyroscopic machine.........
- Gyroscopes and tops. Experiments with a gyroscope. Experience with a top. Wheel experience. Coin experience. Riding a bike without hands. Boomerang experience.........
- Experiments with invisible axes. Experience with paper clips. Rotating a matchbox. Slalom on paper.........
- Rotation changes shape. Cool or damp. Dancing egg. How to put a match.........
- When the water does not pour out. A bit of a circus. Experiment with a coin and a ball. When the water pours out. Umbrella and separator..........
Statics. Equilibrium. Center of gravity
- Vanka-stand up. Mysterious nesting doll.........
- Center of gravity. Equilibrium. Center of gravity height and mechanical stability. Base area and balance. Obedient and naughty egg..........
- Center of gravity of a person. Balance of forks. Fun swing. A diligent sawyer. Sparrow on a branch.........
- Center of gravity. Pencil competition. Experience with unstable balance. Human balance. Stable pencil. Knife at the top. Experience with a ladle. Experience with a saucepan lid.........
Structure of matter
- Fluid model. What gases does air consist of? Highest density of water. Density tower. Four floors.........
- Plasticity of ice. A nut that has come out. Properties of non-Newtonian fluid. Growing crystals. Properties of water and eggshells..........
Thermal expansion
- Expansion of a solid. Lapped plugs. Needle extension. Thermal scales. Separating glasses. Rusty screw. The board is in pieces. Ball expansion. Coin expansion.........
- Expansion of gas and liquid. Heating the air. Sounding coin. Water pipe and mushrooms. Heating water. Warming up the snow. Dry from the water. The glass is creeping.........
Surface tension of a liquid. Wetting
- Plateau experience. Darling's experience. Wetting and non-wetting. Floating razor.........
- Attraction of traffic jams. Sticking to water. A miniature Plateau experience. Soap bubbles..........
- Live fish. Paperclip experience. Experiments with detergents. Colored streams. Rotating spiral.........
Capillary phenomena
- Experience with a blotter. Experiment with pipettes. Experience with matches. Capillary pump.........
Soap bubbles
- Hydrogen soap bubbles. Scientific preparation. Bubble in a jar. Colored rings. Two in one.........
Energy
- Transformation of energy. Bent strip and ball. Tongs and sugar. Photo exposure meter and photo effect.........
- Conversion of mechanical energy into thermal energy. Propeller experience. Bogatyr in a thimble..........
Thermal conductivity
- Experiment with an iron nail. Experience with wood. Experience with glass. Experiment with spoons. Coin experience. Thermal conductivity of porous bodies. Thermal conductivity of gas.........
Heat
-Which is colder. Heating without fire. Absorption of heat. Radiation of heat. Evaporative cooling. Experiment 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 is a heat regulator. Experience with stearin. Creating traction. Experience with scales. Experience with a turntable. Pinwheel on a pin..........
Aggregate states.
- Experiments with soap bubbles in the cold. Crystallization
- Frost on the thermometer. Evaporation from the iron. We regulate the boiling process. Instant crystallization. growing crystals. Making ice. Cutting ice. Rain in the kitchen.........
- Water freezes water. Ice castings. We create a cloud. Let's make a cloud. We boil the snow. Ice bait. How to get hot ice.........
- Growing crystals. Salt crystals. Golden crystals. Large and small. Peligo's experience. Experience-focus. Metal crystals.........
- Growing crystals. Copper crystals. Fairytale beads. Halite patterns. Homemade frost.........
- Paper pan. Dry ice experiment. Experience with socks.........
Gas laws
- Experience on the Boyle-Mariotte law. Experiment on Charles's law. Let's check the Clayperon equation. Let's check Gay-Lusac's law. Ball trick. Once again about the Boyle-Mariotte law..........
Engines
- Steam engine. The experience of Claude and Bouchereau.........
- Water turbine. Steam turbine. Wind engine. Water wheel. Hydro turbine. Windmill toys.........
Pressure
- Pressure of a solid body. Punching a coin with a needle. Cutting through ice.........
- Siphon - Tantalus vase..........
- Fountains. The simplest fountain. Three fountains. Fountain in a bottle. Fountain on the table.........
- Atmospheric pressure. Bottle experience. Egg in a decanter. Can sticking. Experience with glasses. Experience with a can. Experiments with a plunger. Flattening the can. Experiment with test tubes.........
- Vacuum pump made from blotting paper. Air pressure. Instead of the Magdeburg hemispheres. A diving bell glass. Carthusian diver. Punished curiosity.........
- Experiments with coins. Experiment with an egg. Experience with a newspaper. School gum suction cup. How to empty a glass.........
- Pumps. Spray..........
- Experiments with glasses. Mysterious property radishes. Experience with a bottle.........
- Naughty plug. What is pneumatics? Experiment with a heated glass. How to lift a glass with your palm.........
- Cold boiling water. How much does water weigh in a glass? Determine lung volume. Resistant funnel. How to pierce a balloon without it bursting..........
- Hygrometer. Hygroscope. Barometer from a cone......... - Barometer. Aneroid barometer - do it yourself. Balloon barometer. The simplest barometer......... - Barometer from a light bulb.......... - Air barometer. Water barometer. Hygrometer..........
Communicating vessels
- Experience with the painting.........
Archimedes' law. Buoyancy force. Floating bodies
- Three balls. The simplest submarine. Grape experiment. Does iron float.........
- Ship's draft. Does the egg float? Cork in a bottle. Water candlestick. Sinks or floats. Especially for drowning people. Experience with matches. Amazing egg. Does the plate sink? The mystery of the scales.........
- Float in a bottle. Obedient fish. Pipette in a bottle - Cartesian diver..........
- Ocean level. Boat on the ground. Will the fish drown? Stick scales.........
- Archimedes' Law. Live toy fish. Bottle level.........
Bernoulli's law
- Experience with a funnel. Experiment with water jet. Ball experiment. Experience with scales. Rolling cylinders. stubborn leaves.........
- Bendable sheet. Why doesn't he fall? Why does the candle go out? Why doesn't the candle go out? The air flow is to blame.........
Simple mechanisms
- Block. Pulley hoist.........
- Lever of the second type. Pulley hoist.........
- Lever. Gate. Lever scales.........
Oscillations
- Pendulum and bicycle. Pendulum and globe. A fun duel. Unusual pendulum..........
- Torsion pendulum. Experiments with a swinging top. Rotating pendulum.........
- Experiment with the Foucault pendulum. Addition of vibrations. Experiment with Lissajous figures. Resonance of pendulums. Hippopotamus and bird.........
- Fun swing. Oscillations and resonance.........
- Fluctuations. Forced vibrations. Resonance. Seize the moment.........
Sound
- Gramophone - do it yourself..........
- Physics musical instruments. String. Magic bow. Ratchet. Singing glasses. Bottlephone. From bottle to organ.........
- Doppler effect. Sound lens. Chladni's experiments.........
- Sound waves. Propagation of sound.........
- Sounding glass. Flute made from straw. The sound of a string. Reflection of sound.........
- Phone made from a matchbox. Telephone exchange.........
- Singing combs. Spoon ringing. Singing glass.........
- Singing water. Shy wire.........
- Sound oscilloscope..........
- Ancient sound recording. Cosmic voices.........
- Hear the heartbeat. Glasses for ears. Shock wave or firecracker..........
- Sing with me. Resonance. Sound through the bone.........
- Tuning fork. A storm in a teacup. Louder sound.........
- My strings. Changing the pitch of the sound. Ting-ding. Crystal clear.........
- We make the ball squeak. Kazoo. Singing bottles. Choral singing.........
- Intercom. Gong. Crowing glass.........
- Let's blow out the sound. String instrument. Small hole. Blues on bagpipes.........
- Sounds of nature. Singing straw. Maestro, march.........
- A speck of sound. What's in the bag? Sound on the surface. Day of disobedience.........
- Sound waves. Visual sound. Sound helps you see.........
Electrostatics
- Electrification. Electric panty. Electricity is repellent. Dance of soap bubbles. Electricity on combs. The needle is a lightning rod. Electrification of the thread.........
- Bouncing balls. Interaction of charges. Sticky ball.........
- Experience with a neon light bulb. Flying bird. Flying butterfly. An animated world.........
- Electric spoon. St. Elmo's Fire. Electrification of water. Flying cotton wool. Electrification of a soap bubble. Loaded frying pan.........
- Electrification of the flower. Experiments on human electrification. Lightning on the table.........
- Electroscope. Electric Theater. Electric cat. Electricity attracts.........
- Electroscope. Soap bubbles. Fruit battery. Fighting gravity. Battery of galvanic cells. Connect the coils.........
- Turn the arrow. Balancing on the edge. Pushing nuts. Turn on the light.........
- Amazing tapes. Radio signal. Static separator. Jumping grains. Static rain.........
- Film wrapper. Magic figurines. Influence of air humidity. An animated door handle. Sparkling clothes.........
- Charging from a distance. Rolling ring. Crackling and clicking sounds. Wand..........
- Everything can be charged. Positive charge. Attraction of bodies. Static glue. Charged plastic. Ghost leg.........
Introduction
Without a doubt, all our knowledge begins with experiments.
(Kant Emmanuel. German philosopher g.)
Physics experiments introduce students to the diverse applications of the laws of physics in a fun way. Experiments can be used in lessons to attract students’ attention to the phenomenon being studied, when repeating and consolidating educational material, at physical evenings. Entertaining experiments deepen and expand students’ knowledge, contribute to the development logical thinking, instill interest in the subject.
The role of experiment in the science of physics
The fact that physics is a young science
It’s impossible to say for sure here.
And in ancient times, learning science,
We always strived to comprehend it.
The purpose of teaching physics is specific,
Be able to apply all knowledge in practice.
And it’s important to remember – the role of experiment
Must stand in the first place.
Be able to plan an experiment and carry it out.
Analyze and bring to life.
Build a model, put forward a hypothesis,
Striving to reach new heights
The laws of physics are based on facts established experimentally. Moreover, the interpretation of the same facts often changes in the course of the historical development of physics. Facts accumulate through observation. But you can’t limit yourself to them only. This is only the first step towards knowledge. Next comes the experiment, the development of concepts that allow for qualitative characteristics. In order to draw general conclusions from observations and 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 has been found. If a physical law is found, then there is no need to experiment in each individual case; it is enough to perform the appropriate calculations. By experimentally studying quantitative relationships between quantities, patterns can be identified. Based on these laws, 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 experiments, discussion of the features of its setting and the observed results.
Entertaining experiments in physics
The description of the experiments was carried out using the following algorithm:
Name of the experiment Equipment and materials required for the experiment Stages of the experiment Explanation of the experiment
Experiment No. 1 Four floors
Devices 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 five levels above each other. However, it will be more convenient for us to take not a glass, but a narrow glass that widens towards the top.
Pour salted tinted water into the bottom of the glass. Roll up a “Funtik” from paper and bend its end at a right angle; cut off the tip. The hole in the Funtik should be the size of a pin head. 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 onto the salt water.
When the height of the layer of red wine is equal to the height of the layer of colored water, stop pouring the wine. From the second cone, pour sunflower oil into a glass in the same way. From the third horn, pour a layer of colored alcohol.
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Experience No. 2 Amazing candlestick
Devices and materials: candle, nail, 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.
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Figure 3
Explanation of experience
The candle goes out because the bottle is “flown around” with air: the stream 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 candle flame stands.
Experiment No. 4 Spinning snake
Devices and materials: thick paper, candle, scissors.
Stages of the experiment
Cut a spiral out of thick paper, stretch it a little and place it on the end of a curved wire. Hold this spiral above the candle in the rising air flow, the snake will rotate.
Explanation of experience
The snake rotates because air expands under the influence of heat and warm energy is converted into movement.
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Figure 5
Explanation of experience
Water has a higher density than alcohol; it will gradually enter the bottle, displacing the mascara from there. Red, blue or black liquid will rise upward from the bubble in a thin stream.
Experiment No. 6 Fifteen matches on one
Devices and materials: 15 matches.
Stages of the experiment
Place one match on the table, and 14 matches across it so that their heads stick up and their ends touch the table. How to lift the first match, holding it by one end, and all the other matches along with it?
Explanation of experience
To do this, you just need to put another fifteenth match on top of all the matches, in the hollow between them.
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Figure 7
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Figure 9
Experience No. 8 Paraffin motor
Devices and materials: candle, knitting needle, 2 glasses, 2 plates, matches.
Stages of the experiment
To make this motor, we don't need either electricity or gasoline. For this we only need... a candle.
Heat the knitting needle and stick it with their heads into the candle. This will be the axis of our engine. Place a candle with a knitting needle on the edges of two glasses and balance. 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 disrupted, the other end of the candle will tighten 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 go down, drop a drop, it will become lighter, and our motor will start working with all its might; gradually the candle's vibrations will increase more and more.
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Figure 11
Demonstration experiments
1. Diffusion of liquids and gases
Diffusion (from Latin diflusio - spreading, spreading, scattering), the transfer of particles of different nature, caused by the chaotic thermal movement of molecules (atoms). Distinguish between diffusion in liquids, gases and solids
Demonstration experiment “Observation of diffusion”
Devices and materials: cotton wool, ammonia, phenolphthalein, diffusion observation device.
Stages of the experiment
Let's take two pieces of cotton wool. We moisten one piece of cotton wool with phenolphthalein, the other - ammonia. Let's bring the branches into contact. The fleeces are stained in pink due to the phenomenon of diffusion.
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Figure 13
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Figure 15
Let us prove that the phenomenon of diffusion depends on temperature. The higher the temperature, the faster diffusion occurs.
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Figure 17
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Figure 19
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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 the liquid behind the piston under the influence of atmospheric pressure.
To demonstrate the uniform transfer of pressure exerted on a liquid in a closed vessel, it is necessary to use a piston to draw water into the vessel and place the ball tightly on the nozzle. By pushing the piston into the vessel, demonstrate the flow of liquid from the holes in the ball, paying attention to the uniform flow of liquid in all directions.
Winter will begin soon, and with it the long-awaited time. In the meantime, we invite you to keep your child busy with equally exciting experiments at home, because you want miracles not only for New Year, but also every day.
In this article we will talk about experiments that clearly demonstrate to children such physical phenomena as: atmospheric pressure, properties of gases, the movement of air currents and from various objects.
These will cause surprise and delight in your child, and even a four-year-old can repeat them under your supervision.
How to fill a water bottle without hands?
We will need:
- a bowl of cold water, colored for clarity;
- hot water;
- glass bottle.
Pour into the bottle several times hot water so that it warms up well. Turn the empty hot bottle upside down and place it in a bowl of cold water. We observe how water is drawn from a bowl into a bottle and, contrary to the law of communicating vessels, the water level in the bottle is much higher than in the bowl.
Why is this happening? Initially, a well-warmed bottle is filled with warm air. As the gas cools, it contracts, filling a smaller and smaller volume. Thus, a low-pressure environment is formed in the bottle, where water is directed to restore balance, because atmospheric pressure presses on the water from the outside. Colored water will flow into the bottle until the pressure inside and outside the glass vessel is equalized.
Dancing coin
For this experiment we will need:
- a glass bottle with a narrow neck that can be completely blocked by a coin;
- coin;
- water;
- freezer.
Leave the empty open glass bottle in freezer(or outside in winter) for 1 hour. We take out the bottle, moisten the coin with water and place it on the neck of the bottle. After a few seconds, the coin will begin to jump on the neck and make characteristic clicks.
This behavior of the coin is explained by the ability of gases to expand when heated. Air is a mixture of gases, and when we took the bottle out of the refrigerator it was filled with cold air. At room temperature, the gas inside began to heat up and increase in volume, while the coin blocked its exit. So the warm air began to push out the coin, and in due time it began to bounce on the bottle and click.
It is important that the coin is wet and fits tightly to the neck, otherwise the trick will not work and warm air will freely leave the bottle without tossing a coin.
Glass - sippy cup
Invite your child to turn a glass filled with water over so that the water does not spill out of it. Surely the baby will refuse such a scam or will pour water into the basin at the first attempt. Teach him the next trick. We will need:
- glass of water;
- a piece of cardboard;
- basin/sink for safety net.
Cover the glass of water with cardboard and hold it last hand— turn the glass over, and then remove your hand. It is better to carry out this experiment over a basin/sink, because... If you keep the glass upside down for a long time, the cardboard will eventually get wet and water will spill. It is better not to use paper instead of cardboard for the same reason.
Discuss with your child: why does the cardboard prevent water from flowing out of the glass, since it is not glued to the glass, and why does the cardboard not immediately fall under the influence of gravity?
Do you want to play with your child easily and with pleasure?
When wet, cardboard molecules interact with water molecules, attracting each other. From this moment on, water and cardboard interact as one. In addition, wet cardboard prevents air from entering the glass, which prevents the pressure inside the glass from changing.
At the same time, not only the water from the glass presses on the cardboard, but also the air from outside, which forms the force of atmospheric pressure. It is atmospheric pressure that presses the cardboard to the glass, forming a kind of lid, and prevents water from spilling out.
Experiment with a hairdryer and a strip of paper
We continue to surprise the child. We build a structure from books and attach a strip of paper to them on top (we did this with tape). Paper hangs from the books as shown in the photo. You choose the width and length of the strip based on the power of the hair dryer (we took 4 by 25 cm).
Now turn on the hair dryer and direct the air stream parallel to the lying paper. Despite the fact that the air does not blow on the paper, but next to it, the strip rises from the table and develops as if in the wind.
Why does this happen and what makes the strip move? Initially, the strip is acted upon by gravity and pressed by atmospheric pressure. The hairdryer creates a strong air flow along the paper. In this place, a zone of low pressure is formed towards which the paper is deflected.
Shall we blow out the candle?
We begin to teach the baby to blow before he is one year old, preparing him for his first birthday. When the child has grown up and has fully mastered this skill, offer it to him through a funnel. In the first case, positioning the funnel so that its center corresponds to the level of the flame. And the second time, so that the flame is along the edge of the funnel.
Surely the child will be surprised that all his efforts in the first case will not give the desired result in the form of an extinguished candle. In the second case, the effect will be immediate.
Why? When air enters the funnel, it is evenly distributed along its walls, so the maximum flow rate is observed at the edge of the funnel. And in the center the air speed is low, which prevents the candle from going out.
Shadow from a candle and from a fire
We will need:
- candle;
- flashlight.
We light the fire and place it near a wall or other screen and illuminate it with a flashlight. A shadow from the candle itself will appear on the wall, but there will be no shadow from the fire. Ask your child why this happened?
The thing is that fire itself is a source of light and transmits other light rays through itself. And since a shadow appears when an object is illuminated from the side and does not transmit rays of light, fire cannot produce a shadow. But it's not that simple. Depending on the substance being burned, the fire can be filled with various impurities, soot, etc. In this case, you can see a blurry shadow, which is precisely what these inclusions provide.
Did you like the selection of experiments to do at home? Share with your friends by clicking on the social networking buttons so that other mothers can please their kids with interesting experiments!
Entertaining experiences.
Extracurricular activity for middle classes.
Extracurricular event in physics for middle classes “Entertaining experiments”
Objectives of the event:Develop cognitive interest, interest in physics;
- develop competent monologue speech using physical terms, develop attention, observation, and the ability to apply knowledge in a new situation;
- teach children to communicate in a friendly manner.
Teacher: Today we will show you interesting experiments. Watch carefully and try to explain them. Those who excel in their explanations will receive prizes - good and excellent grades in physics.
(9th grade students show experiments, and 7-8th grade students explain)
Experiment 1 “Without getting your hands wet”
Equipment: plate or saucer, coin, glass, paper, matches.
How to do it: Place a coin on the bottom of a plate or saucer and pour in some water. How to get a coin without even getting your fingertips wet?
Solution: Light the paper and place it in the glass for a while. Turn the heated glass upside down and place it on a saucer next to the coin.
As the air in the glass heats up, its pressure will increase and some of the air will escape. After some time, the remaining air will cool and the pressure will decrease. Under the influence of atmospheric pressure, the water will enter the glass, releasing the coin.
Experiment 2 “Lifting a plate of soap”
Equipment: plate, piece of laundry soap.
Procedure: Pour water into a plate and drain immediately. The surface of the plate will be damp. Then, pressing the bar of soap firmly against the plate, turn it several times and lift it up. At the same time, the plate will rise with soap. Why?
Explanation: The lifting of the dish with soap is explained by the attraction of the molecules of the dish and soap.
Experiment 3 “Magic water”
Equipment: a glass of water, a sheet of thick paper.
Conduct: This experiment is called “Magic Water”. Fill a glass with water to the brim and cover it with a sheet of paper. Let's turn the glass over. Why doesn't water pour out of an upside down glass?
Explanation: Water is held by atmospheric pressure, i.e. atmospheric pressure is greater than the pressure produced by water.
Notes: The experiment works better with a thick-walled vessel.
When turning the glass over, the sheet of paper must be held with your hand.
Experiment 4 “Untearable paper”
Equipment: two tripods with couplings and legs, two paper rings, a staff, a meter.
Carrying out: We hang the paper rings on tripods at the same level. We'll put a rail on them. When struck sharply with a meter or metal rod in the middle of the rack, it breaks, but the rings remain intact. Why?
Explanation: The interaction time is very short. Therefore, the rack does not have time to transfer the received impulse to the paper rings.
Notes: The width of the rings is 3 cm. The rail is 1 meter long, 15-20 cm wide and 0.5 cm thick.
Experience 5 “Heavy Newspaper”
Equipment: strip 50-70 cm long, newspaper, meter.
Conduct: Place a slate on the table and a fully unrolled newspaper on it. If you slowly apply pressure to the hanging end of the ruler, it goes down, and the opposite one rises along with the newspaper. If you sharply hit the end of the rail with a meter or a hammer, it breaks, and the opposite end with the newspaper does not even rise. How to explain this?
Explanation: Atmospheric air exerts pressure on the newspaper from above. By slowly pressing on the end of the ruler, air penetrates under the newspaper and partially balances the pressure on it. With a sharp impact, due to inertia, the air does not have time to instantly penetrate under the newspaper. The air pressure on the newspaper from above is greater than from below, and the rail breaks.
Notes: The rail should be placed so that its end hangs 10 cm. The newspaper should fit snugly against the rail and table.
Experience 6
Equipment: tripod with two couplings and legs, two demonstration dynamometers.
Carrying out: Let's attach two dynamometers - devices for measuring force - on a tripod. Why are their readings the same? What does this mean?
Explanation: bodies act on each other with forces equal in magnitude and opposite in direction. (Newton's third law).
Experience 7
Equipment: two sheets of paper identical in size and weight (one of them is crumpled).
Carrying out: Let's release both sheets at the same time from the same height. Why does a crumpled piece of paper fall faster?
Explanation: A crumpled piece of paper falls faster because there is less air resistance acting on it.
But in a vacuum they would fall simultaneously.
Experiment 8 “How quickly a candle goes out”
Equipment: glass vessel with water, stearin candle, nail, matches.
Conduct: Light a candle and lower it into a vessel with water. How quickly will the candle go out?
Explanation: The flame appears to be filled with water as soon as the section of the candle protruding above the water burns and the candle goes out.
But, as it burns, the candle decreases in weight and floats up under the influence of Archimedean force.
Note: Attach a small weight (nail) to the end of the candle from below so that it floats in the water.
Experiment 9 “Fireproof paper”
Equipment: metal rod, strip of paper, matches, candle (alcohol lamp)
How to carry out: Wrap the rod tightly with a strip of paper and place it in the flame of a candle or alcohol lamp. Why doesn't the paper burn?
Explanation: Iron, having good thermal conductivity, removes heat from the paper, so it does not catch fire.
Experiment 10 “Fireproof scarf”
Equipment: tripod with clutch and foot, alcohol, handkerchief, matches.
How to do it: Hold a handkerchief (previously moistened with water and wrung out) in the tripod foot, pour alcohol on it and set it on fire. Despite the flames engulfing the scarf, it will not burn. Why?
Explanation: The heat released during the combustion of alcohol was completely used to evaporate the water, so it cannot ignite the fabric.
Experiment 11 “Fireproof thread”
Equipment: tripod with coupling and foot, feather, regular thread and thread soaked in a saturated solution of table salt.
How to do it: Hang a feather on a thread and set it on fire. The thread burns and the feather falls. Now let’s hang a feather on a magic thread and set it on fire. As you can see, the magic thread burns out, but the feather remains hanging. Explain the secret of the magic thread.
Explanation: The magic thread was soaked in a solution of table salt. When the thread is burned, the feather is held on by fused crystals of table salt.
Note: The thread should be soaked 3-4 times in a saturated salt solution.
Experiment 12 “Water is boiling in a paper pan”
Equipment: tripod with coupling and foot, paper pan with strings, alcohol lamp, matches.
How to do it: Hang the paper pan on a tripod.
Is it possible to boil water in this pan?
Explanation: All the heat released during combustion is used to heat the water. In addition, the temperature of the paper pan does not reach the ignition temperature.
Interesting questions.
Teacher: While the water is boiling, you can ask the audience questions:
What grows upside down? (icicle)
I swam in the water, but remained dry. (Goose, duck)
Why don't waterfowl get wet in water? (The surface of their feathers is covered with a thin layer of fat, and water does not wet the fatty surface.)
Even a child can lift him from the ground, but not even a strong man can throw him over a fence. (Pushinka)
The window is broken during the day and put back in place at night. (Ice hole)
The results of the experiments are summed up.
Grading.
2015-
Good afternoon, guests of the Eureka Research Institute website! Do you agree that knowledge supported by practice is much more effective than theory? Entertaining experiments in physics will not only provide great entertainment, but will also arouse a child’s interest in science, and will also remain in memory much longer than a paragraph in a textbook.
What can experiments teach children?
We bring to your attention 7 experiments with explanations that will definitely raise the question in your child “Why?” As a result, the child learns that:
- By mixing 3 primary colors: red, yellow and blue, you can get additional ones: green, orange and purple. Have you thought about paints? We offer you another one, unusual way make sure of this.
- Light reflects off a white surface and turns into heat if it hits a black object. What could this lead to? Let's figure it out.
- All objects are subject to gravity, that is, they tend to a state of rest. In practice it looks fantastic.
- Objects have a center of mass. And what? Let's learn to benefit from this.
- Magnet is an invisible but powerful force of some metals that can give you the abilities of a magician.
- Static electricity can not only attract your hair, but also sort out small particles.
So let's make our kids proficient!
1. Create a new color
This experiment will be useful for preschoolers and junior schoolchildren. To conduct the experiment we will need:
- flashlight;
- red, blue and yellow cellophane;
- ribbon;
- white wall.
We conduct the experiment near a white wall:
- We take a lantern, cover it first with red and then yellow cellophane, and then turn on the light. We look at the wall and see an orange reflection.
- Now we remove the yellow cellophane and put a blue bag on top of the red one. Our wall is illuminated in purple.
- And if we cover the lantern with blue and then yellow cellophane, then we will see a green spot on the wall.
- This experiment can be continued with other colors.
2. Black color and sunbeam: explosive combination
To carry out the experiment you will need:
- 1 transparent and 1 black balloon;
- magnifying glass;
- ray of sunshine.
This experience will require skill, but you can do it.
- First you need to inflate a transparent balloon. Hold it tightly, but do not tie the end.
- Now, using the blunt end of a pencil, push the black balloon halfway inside the transparent one.
- Inflate the black balloon inside the clear one until it fills about half the volume.
- Tie the end of the black ball and push it into the middle of the clear ball.
- Inflate the transparent balloon a little more and tie the end.
- Position the magnifying glass so that the sun's ray hits the black ball.
- After a few minutes, the black ball will burst inside the transparent one.
Tell your child that transparent materials allow sunlight to pass through, so we can see the street through the window. A black surface, on the contrary, absorbs light rays and turns them into heat. This is why it is recommended to wear light-colored clothing in hot weather to avoid overheating. When the black ball heated up, it began to lose its elasticity and burst under the pressure of the internal air.
3. Lazy ball
The next experiment is a real show, but you will need to practice to carry it out. The school gives an explanation for this phenomenon in the 7th grade, but in practice this can be done even in preschool age. Prepare the following items:
- plastic glass;
- metal dish;
- cardboard sleeve from under toilet paper;
- tennis ball;
- meter;
- broom.
How to conduct this experiment?
- So, place the glass on the edge of the table.
- Place a dish on the glass so that its edge on one side is above the floor.
- Place the base of the toilet paper roll in the center of the dish directly above the glass.
- Place the ball on top.
- Stand half a meter from the structure with a broom in your hand so that its rods are bent towards your feet. Stand on top of them.
- Now pull back the broom and release it sharply.
- The handle will hit the dish, and it, together with the cardboard sleeve, will fly to the side, and the ball will fall into the glass.
Why didn't it fly away with the rest of the items?
Because, according to the law of inertia, an object that is not acted upon by other forces tends to remain at rest. In our case, the ball was only affected by the force of gravity towards the Earth, which is why it fell down.
4. Raw or cooked?
Let's introduce the child to the center of mass. To do this, let's take:
· cooled hard-boiled egg;
· 2 raw eggs;
Invite a group of children to distinguish a boiled egg from a raw one. However, eggs cannot be broken. Say that you can do it without fail.
- Roll both eggs on the table.
- An egg that rotates faster and at a uniform speed is a boiled one.
- To prove your point, crack another egg into a bowl.
- Take a second raw egg and a paper napkin.
- Ask a member of the audience to make the egg stand on the blunt end. No one can do this except you, since only you know the secret.
- Just vigorously shake the egg up and down for half a minute, then easily place it on a napkin.
Why do eggs behave differently?
They, like any other object, have a center of mass. That is, different parts of an object may not weigh the same, but there is a point that divides its mass into equal parts. In a boiled egg, due to its more uniform density, the center of mass remains in the same place during rotation, while in raw egg it moves along with the yolk, making it difficult to move. In a raw egg that has been shaken, the yolk drops to the blunt end and the center of mass is there, so it can be placed.
5. “Golden” mean
Invite the children to find the middle of the stick without a ruler, but just by eye. Evaluate the result using a ruler and say that it is not entirely correct. Now do it yourself. A mop handle is best.
- Raise the stick to waist level.
- Lay her down on 2 index fingers, keeping them at a distance of 60 cm.
- Move your fingers closer together and make sure the stick doesn't lose its balance.
- When your fingers come together and the stick is parallel to the floor, you have reached your goal.
- Place the stick on the table, keeping your finger on the desired mark. Use a ruler to make sure you have completed the task accurately.
Tell your child that you found not just the middle of the stick, but its center of mass. If the object is symmetrical, then it will coincide with its middle.
6. Zero gravity in a jar
Let's make the needles hang in the air. To do this, let's take:
- 2 threads of 30 cm;
- 2 needles;
- transparent tape;
- liter jar and lid;
- ruler;
- small magnet.
How to conduct the experiment?
- Thread the needles and tie the ends with two knots.
- Tape the knots to the bottom of the jar, leaving about 1 inch (2.5 cm) to the edge.
- From the inside of the lid, glue the tape in the form of a loop, with the sticky side facing out.
- Place the lid on the table and glue a magnet to the hinge. Turn the jar over and screw on the lid. The needles will hang down and be drawn towards the magnet.
- When you turn the jar upside down, the needles will still be drawn to the magnet. You may need to lengthen the threads if the magnet does not hold the needles upright.
- Now unscrew the lid and place it on the table. You are ready to perform the experiment in front of an audience. As soon as you screw on the lid, the needles from the bottom of the jar will shoot up.
Tell your child that a magnet attracts iron, cobalt and nickel, so iron needles are susceptible to its influence.
7. “+” and “-”: beneficial attraction
Your child has probably noticed how hair is magnetic to certain fabrics or combs. And you told him that it was all to blame static electricity. Let's do an experiment from the same series and show what else the “friendship” of negative and positive charges can lead to. We will need:
- paper towel;
- 1 tsp. salt and 1 tsp. pepper;
- spoon;
- balloon;
- woolen item.
Experiment stages:
- Place a paper towel on the floor and sprinkle the salt and pepper mixture on it.
- Ask your child: how to separate salt from pepper now?
- Rub the inflated balloon on a woolen item.
- Season it with salt and pepper.
- The salt will remain in place, and the pepper will be magnetized to the ball.
After rubbing against the wool, the ball acquires a negative charge, which attracts positive ions from the pepper. The salt's electrons are not so mobile, so they do not react to the approach of the ball.
Experiences at home are valuable life experiences
Admit it, you yourself were interested in watching what was happening, and even more so for the child. By performing amazing tricks with the simplest substances, you will teach your child:
- trust you;
- see the amazing in everyday life;
- It’s exciting to learn the laws of the world around you;
- develop diversified;
- learn with interest and desire.
We remind you once again that developing a child is simple and you don’t need a lot of money and time. See you soon!
