Amazing But Simple Science Experiments

Starting this thread to post some simple science experiments that u can do at home with available materials.
I have started this thread in the hope that it will be useful to students.

Leave a bowl of water for a long while without pouring the water out (probably two months). Result is shown in the following image (warning: profanity in image and ickiness)

http://imgur.com/Bu7xY.jpg

I guess it shows how fuzzy things begin to grow when you don't clean for a long while.

Originally Posted by Pen_it_Black

Leave a bowl of water for a long while without pouring the water out (probably two months). Result is shown in the following image (warning: profanity in image and ickiness)

http://imgur.com/Bu7xY.jpg

I guess it shows how fuzzy things begin to grow when you don't clean for a long while.

haha...ew...what the hell >_<

Place a pair of binoculars in an open window in the direct path of the sun’s rays.
Stand a mirror in front of one eyepiece so that it throws an image of the sun on to the opposite wall of the room. Adjust the mirror until the image is sharp, and darken the room.
You would risk damaging your eyes if you looked directly at the sun through
binoculars, but you can view the bright disc on the wall as large and clear as in the movies. Clouds and birds passing over can also be distinguished and. if the binoculars are good even sunspots. These are a few hot areas on the glowing sphere, some so big that many terrestrial globes could fit into them. Because of the earth’s rotation, the sun’s image moves quite quickly across the wall. Do not forget to re-align the binoculars from time to time onto the sun. The moon and stars cannot be observed in this way because the light coming from them is too weak.

P.S Adult supervision is required.

The Sun Clock
Place a flowerpot with a long stick fixed into the hole at the bottom in a spot, which is sunny, all day. The stick’s shadow moves along the rim of the pot as the sun moves. Each hour by the clock mark the position of the shadow on the pot. If the sun is shining, you can read off the time. Because of the rotation of the earth the sun apparently passes over us in a semi-circle. In the morning and evening its shadow strikes the pot superficially, while; it midday, around 12 o’clock, the light incidence is greatest. The shadow can be seen particularly clearly on the sloping wall of the pot.

P.S Adult supervision is required

Plant a sprouting potato in moist soil in a pot. Place it in the corner of a shoe box and cut a hole in the opposite side. Inside stick two partitions, so that a small gap is left. Close the box and place it in a window. After a couple of days the shoot has found its way through the dark maze to the light.

Plants have light-sensitive cells, which guide the direction of growth. Even the minimum amount of light entering the box causes the shoot to bend. It looks quite white, because the important green colouring material, chlorophyll, necessary for healthy growth, cannot be formed in the dark.

P.S Adult Supervision is a Must for all Experiments

Dilute red and green fountain pen inks with water and fill two glass tubes each with one colour. Split the stem of a flower with white petals, e.g. a dahlia, rose or carnation, and place one end in each tube. The fine veins of the plant soon become coloured, and after several hours the flower is half-red and half blue.

The coloured liquid rises through the hair-fine channels by which, the water and food are transported. The dye is stored in the petals while most of the water is again given off

P.S : ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

If you ever want to write a secret message on paper, simply use vinegar, lemon, or onion juice, as the invisible ink. Write with it as usual on white writing paper. After it dries the writing is invisible. The person who receives the letter must know that the paper has to be held over a candle flame: the writing turns brown and is clearly visible.

Vinegar, and lemon or onion juice, cause a chemical change in the paper to a substance similar to cellophane. Because its ignition temperature is lower than that of the paper, the parts written on singe

P.S:ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS.

Stick finger-length pieces of copper and zinc wire one at a time into a raw potato. If you hold an earphone on the wires, you will hear distinct crackling.

An electric current causes the noise. The potato and wires produce an electric current in the same way as a torch battery, but only a very weak one. The sap of the potato reacts with the metals in a chemical process and also produces electrical energy. We speak of a galvanic cell because the Italian doctor Galvani first observed this process in a similar experiment in 1789.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Place several copper coins and pieces of sheet zinc of the same size alternately above one another, and between each metal pair insert a piece of blotting paper soaked in salt water. Electrical energy, which you can detect, is set free. Wind thin, covered copper wire about 50 times round a compass, and holds one of the bare ends on the last coin and one on the last zinc disk. The current causes a deflection of the compass needle.

In a similar experiment the Italian physicist Volta obtained a current. The salt solution acts on the metal like the sap in the potato in the previous experiment

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Push two pencil leads through the short sides of a matchbox, just above the base. Scrape off some of the surface, and do the same with a shorter lead, which you lay across the top. Connect the microphone with a battery and earphone in the next room. (You can take the earphone from a transistor radio.) Hold the box horizontal and speak into it. Your words can be heard clearly in the earphone.

The current flows through the graphite

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Blow up some balloons, tie them up and rub them for a short time on a woollen pullover. If you put them on the ceiling, they will remain there for hours.

The balloons become electrically charged when they are rubbed, that is, they remove minute, negatively charged particles, and called electrons, from the pullover. Because electrically charged bodies attract those, which are uncharged, the balloons cling to the ceiling until the charges gradually become equal. This generally takes hours in a dry atmosphere because the electrons only flow slowly into the ceiling, which is a poor conductor.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Once more rub a plastic spoon with a woollen cloth. Turn the water tap on gently and hold the spoon near the fine jet. At this point, the jet will be pulled towards the spoon in a bow.

The electric charge attracts the uncharged water particles. However, if the water touches the spoon, the spell is broken. Water conducts electricity and draws the charge from the spoon. Tiny water particles suspended in the air also take up electricity.

Therefore experiments with static electricity always work best on clear days and in centrally heated rooms.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Blow two balloons right up and join them with string. Rub both on a woolen pullover and let them hang downwards from the string. They are not attracted, as you might expect, but float away from each other.

Both balloons have become negatively charged on rubbing because they have taken electrons from the pullover, which has now gained a positive charge. Negative and positive charges attract each other, so the balloons will stick to the pullover. Similar charges, however, repel one another, so the balloons try hard to get away from each other.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Lay a sheet of drawing paper over a magnet - of course you already know how to make a magnet - and scatter iron filings on it. Tap the paper lightly, and a pattern forms.

The filings form into curved lines and show the direction of the magnetic force. You can make the pattern permanent. Dip the paper into melted candle wax and let it cool. Scatter the iron filings on it. If you hold a hot iron
over the paper after the formation of the magnetic lines, the field lines, the pattern will be fixed.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

You can immerse a pocket-handkerchief in water, without it getting
wet: stuff the handkerchief firmly into a tumbler and immerse it upside down in the water.

Air is certainly invisible, but it nevertheless consists of minute particles, which fill the available space.

So air is also enclosed in the upturned glass, and it stops the water entering. If, however, you push the glass deeper, you will see that some water does enter, due to the increasing water pressure, which compresses the air slightly. Diving bells and caissons, used under water, work on the same principle.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Fill a glass to overflowing with water and lay a postcard on it. Support the card with one hand, turn the glass upside down and remove your hand from the card. it remains on the glass, and allows no water to escape.

With a glass of normal height, a weight of water of about 2 ounces presses on each square inch of card. On the other hand the pressure of air from below is about one- hundred times as great on each square inch, and presses the card so firmly against the glass that no air can enter at the side and so no water can flow out

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Hold an empty bottle horizontal and place a small paper ball just inside its neck. Try to blow the ball into the bottle. You cannot! Instead of going into the bottle, the ball flies towards your face.

When you blow, the air pressure in the bottle is increased, and at the same time there is a partial vacuum just inside the neck. The pressures become equalised so that the ball is driven out as
from an airgun

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

right rhythm with fake sign, , ,

Place two porcelain egg-cups one in front of the other, with an egg in the front one. Blow hard from above on to the edge of the filled cup. Suddenly the egg rises, turns upside down and falls into the empty cup. Because the egg shell is rough, it does not lie flat against the smooth wall of the egg-cup. Air is blown through the gap into the space under the egg, where it becomes compressed. When the pressure of the cushion is great enough,
it lifts the egg upwards.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

If you stand behind a tree trunk or a round pillar on a windy day, you will notice that if offers no protection, and a lighted match will be extinguished. A small experiment at home will confirm this: blow hard against a bottle which has a burning candle standing behind it, and the flame goes out at once. The air current divides on hitting the bottle, clings to the sides, and joins up again behind the bottle with its strength hardly
reduced. It forms an eddy which hits the flame. You can put out a lighted candle placed behind two bottles in this way, if you have a good blow.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Many physical experiments seem like magic, but there are logical explanations and laws for all the strange occurrences. Stick a thumbtack through the middle of a halved postcard. Hold it under a cotton spool so that the pin projects into the hole and blow hard down the hole. If you manage to loosen the card, you really expect into fall. In fact, it remains hovering under the spool.

Bernoulli’s law explains this surprising result. The air current goes through at high speed between the card and the spool, producing a lower pressure, and the normal air pressure pushes the card from below against the spool. The ascent of an aircraft takes place in a similar manner. The air flows over the arched upper surface of the wings faster than over the flat under-surface, and therefore the air pressure above the wings is reduced, providing lift.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Pour some coloured water into a bottle. Push a drinking straw through a hole bored in the cork so that it dips into the water. Seal the cork with glue. If you place your hands firmly on the bottle, the water rises up the straw.

The air enclosed in the bottle expands on heating and presses on the water surface. The displaced water escapes into the straw and shows the degree of heating by its position. You can fix a scale on the side of the bottle.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Roll a paper napkin into a tube and twist up the top. Stand it upright and light the tip. While the lower part is still burning, the ash formed rises into the air. Take care!

The air enclosed by the paper is heated by the flame and expands. The light balloon-like ash residue experiences surprising buoyancy because the hot air can escape, and the air remaining in the balloon becomes correspondingly lighter. Very fine napkins are not suitable for the experiment because the ash formed is not firm enough.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Put spoons made of steel, silver, and plastic and a glass rod into a glass. Fix a dry pea at the same height on each handle with a dab of butter. In which order will the peas fall if you pour boiling water into the glass?
The butter on the silver spoon melts very quickly and releases its pea first. The peas from the steel spoon and the glass rod fall later, while that on the plastic spoon does not move. Silver is by far the best conductor of heat, while plastic is a very poor conductor, which is why saucepans, for example, often have plastic handles

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Three different coins lie in a plastic dish. You close your eyes while another person takes out one coin, holds it for several seconds in his closed hand, and puts it back. Now hold the coins one after the other briefly to your upper lip and find out immediately, to everyone’s astonishment, which coin
was taken from the dish. Since metals are very good conductors of heat, the coin warms up immediately in the hand. But plastic is a poor conductor, so hardly any heat is lost to the dish when the coin is put
back. The upper lip is particularly sensitive and reveals the smallest temperature difference in the coins, so that you can detect the right one immediately.
Before the trick is repeated it is a good idea to lay the coins on a cold stone floor to conduct away the heat.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Warm the base of a candle stump and stick it in a bowl. Fill the bowl with cold water up to the rim of the candle. If you light the wick it burns until it is under the surface of the water. Then the candle flame hollows out a deep funnel. An extremely thin wail of wax remains standing round the flame and stops the water from extinguishing it. The water takes so much heat from the candle that its outer layer does not reach its melting
point, and the wax there cannot evaporate and burn.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Fix a dry pinecone on to a small piece of wood with sealing wax or glue. Stick a pin into one of the central scales and place a straw over it. Put the cone out-of- doors, protected from the rain. The straw moves according to the state of the weather. Fix up a scale.

This simple hygrometer was built by nature. The pinecone closes when it is going to rain, to protect the seeds from damp. The outside of the scales absorbs the moisture in the air, swells up and bends - a process which you can also observe with a piece of paper which is wet on one side.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Coat a strip of writing paper two inches long with glue and roll it onto a sewing needle. Stick a strip of shiny photographic paper about 3 inch wide and one foot long onto its end so that its shiny surface faces the glue-covered side of the writing paper. The filmstrip is rolled round the needle like a clock spring. Punch a small hole through the middle of the bottom and lid of a furniture polish tin, and also air holes in the bottom. File off the metal projections formed. Push the needle through the central holes and stick the end of the filmstrip firmly to the side of the tin.

Fix a paper pointer in front of the needle with a cork disk, and a bead behind it. The gelatin layer of the photographic film expands - in contrast to the paper layer - with increased air humidity, causing it to wind up sharply, and move the pointer to the right. When the humidity of the air falls, the pointer returns to the left.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS

Stretch a strip of cellophane (not plastic foil), 1 inch wide, tightly over a soup plate and fasten the ends with adhesive tape. Lay on the middle of the strip an average-sized coin and pour water into the dish up to about 3-inch under the coin.

The coin sinks slowly and reaches the water after several minutes.

The water vaporises, the cellophane absorbs the water particles from the air and expands until it reaches the water. But strangely enough it soon begins to tighten again, and the coin rises again slowly to its original position.

P.S: ADULT SUPERVISION IS A MUST FOR ALL EXPERIMENTS