Saturday, February 20, 2010

Strong Czech Eggs

Experiments made by Jiří´s brother

Find more videos like this on Have fun with simple experiments

How to make refractory paper?

Home made video from Justyna&Grzegorz

To our experiment we need:
metal cup, piece of paper and lighter.

Heat is transfered from paper belt to metal cup. That's why paper can not reach ignition temperature.

Tuesday, February 16, 2010

Combustion of a candle (Combustión de una vela)

A soup bowl
A candle
A narrow glass

We fill the plate with water
We light the candle and put into the plate so that the glass doesn´t touch the flame
We place a glass on the candle. We wait for a moment and we see that the flame goes out, and them comes into the water in the glass.

When we light the candle, it produces a combustion reaction: the wax of the candle reacts with the oxygen of the air and produces carbon dioxide and water steam. We can see that inside of the glass appear a few drops of water. It is the water steam produced in the combustion of a candle that is condensed in the walls of the containers.

In the reaction the gas is consumed, the oxygen that forms a part of the air, but other two are formed, the carbon dioxide and the water steam. The volume of the gas produced, is smaller than the volume of the oxygen that is consumed.
The results is that in the interior of the glass the pressure is reduced and because of that the water goes up until the interior pressure is reduced and because of that the water goes up until the interior pressure is equal to the interior one

by Amelia and Laura

Sunday, February 14, 2010

Vinegar&baking soda

Experiment from Kinga & Żaneta
We pour vinegar into a bottle and fill the balloon with baking soda. Then we're stretching a balloon on the bottle and turn it up side down. The balloon grows up by itself. In this experiment carbon dioxide is created.
Next we let it into the bottle. The burning match will dejeckt in this bottle, because there isn't any oxygen.
So when we remove the carbon dioxide from the bottle, the match will burn because there is oxygen inside now.

Saturday, February 13, 2010

Flying cork

Experiment from Ania&Adriej

To ours experiment we need a water, a stand, a cork, a test tube and a burner. We pour water into the tube and dose it with a cork. Then we put this on a stand and burner under it. We heat the water. The cork fires out because steam in tube pushes the cork under high pressure.

Potential Energy - Powered Car

Our car is powered by potential energy of a weight. Pull up the weight by rotating back wheels. Potential energy of the weight goes up. Release the weight, potential energy of the weight transforms into kinetic energy of the car. The car moves.

Soap-Powered Boat

1.Cut a boat out of the index card.
2.Cut a small slot in the rear of the boat for the engine. That's where the fuel (the dishwashing soap) will go.
3.Float the boat in the container of water.
4.Pour a few drops of dishwashing soap in the engine and watch it go.
Why did the boat move? The attraction between water particles at the water's surface produces surface tension. This gives the surface a skin-like quality. Think of this thin skin-like quality like a balloon. Adding liquid soap is like popping the balloon. You break the surface tension; the thin "skin" breaks and pulls away to the sides. If there's something floating on these water particles, like the boat, it goes along for the ride. After the whole "skin" breaks the boat sinks.

Snow and salt

Put snow into a pot. Take a glass plate and wash it. Sprinkle a spoon of salt into the pot. Be careful not to throw any salt on the plate. Wait for a while and look at the pot. The pot is frozen onto the plate.

The temperature of the snow has gone down. The salt destroy the crystals of snow and makes them melt. Lots of heat is needed to melt the snow. It is taken from everything around. That´s why the temperature drops.

Water rose

Cut out a flower shape from smooth colour paper. Fold the petals firmly inwards. Put the rose on the water. Paper consists mainly of plant fibre, which is composed of extremely fine tubes. The water rises in these so-called capillary tubes. The paper swells, and the petals of the paper rose rise up.

Ice hook

Put an ice cube in a glass of water.
Take a match, lay it across the ice and try to lift the ice up with the match.
Lay the match on the ice again and scatter a pinch of salt over the match.
Count to 10 and lift the match.

Salt water does not freeze as easily as ordinary water, and scattering salt on ice makes it melt. When a substance melts, heat is consumed at the same time. This heat is taken from the moisture under the match, where no salt fell, in this case – and it freezes.

Sunday, February 7, 2010

ETwinning Conference 2010

This year, the eTwinning Conference 2010 has taken place in Seville (Spain).

Four partners of our project were invited to the conference: Claudia (Romania), Irena (Lithuania), Vladimíra (Czech Republic) and Manuel (Spain). It is unfortunate that Elżbieta (Poland) could not be in the Conference. Maybe next year.

Perhaps our students may encounter one day. It would be great.

Wednesday, February 3, 2010

How to do invisible ink?

Experiment from Grzegorz&Justyna

It happens because hydrogen contained in the lemon juice, affixed to a piece of paper under the influence of fire reacts and stained with brown.

Flotabilidad y equilibrio (Floatage and balance)

To make our experiment we need a glass bottle, marbles, pieces of white cork and a recipient with water.

First we put the marbles at the bottom of the glass bottle and we put the cork over. We put the cover and we put the boatinto the water. When can check that the bottle fleets and keep the balance.

We repeated the experiment just viceverse and we can check that the bottle fleets but doesn´t keep the balance.

The glass boat fleet in all cases because its weight (P) is equal to its push(E).

Respect to the balance we should notice the situation of weight and push

When we put the marbles at the bottom the centre of gravity is so down. When the boat inclines it´s generates a couple of strength which makes the boat keep the balance.

When we put the pieces of white cork at the bottom the centre of gravity is so high. When the boat inclines it´s generates a couple of strength which makes the boat doesn´t keep the balance

The more down we put the centre of gravity the more blanced.

by Fernando and Enrique