Obedient pole

We need: a piece of fabric, a pole, a glass, a piece of cork, a needle, a bottle

I put a needle into a piece of cork. The sharp end of the needle is outside of the cork. I put the cork in a neck of a bootle. I put a glass on the needle. I charge a pole by rubbing with a piece of fabric. I put the pole on the glass. I put my thumb close to the pole and make it move.

Electrostatics by Pavla

Electrostatics by Ondra

We need a plastic folder and small pieces of paper. Rub a piece of fabric with the plastic folder. Put the plastic folder above pieces of paper. The small pieces of paper are drawing up to the folder because the folder is charged and electrons and nucleons in the pieces of paper form dipoles.

Aluminium rod and heat

Jan´s experiment from the Czech team
Pierce the middle of an aluminum rod, slightly above the center of gravity. Hang the rod on a revolving stand. Stick a glass-headed pin in a cork stopper, and use this as the axis of rotation. Put the rod in the horizontal position. Make one side hot. As the rod is heated, this raises the energy of particles and thus increases their weight. So the heated arm is heavier and sinks down :-).
Truth be told. Heat extends the aluminum rod; the center of gravity moves to cause a new rod position, with a stable center of gravity below the point of suspension.

Egg into Bottle

You will need: a glass bottle a boiled egg hot water

1. Peel the boiled egg
2. Pour hot water in a bottle for a while
3. Put the egg immediately on the top of the bottle
4. The egg goes through

When you pour warm water into the bottle, the air inside the bottle expands. The egg goes through because the air pressure around pushes the egg inside the bottle.

Hot Air

We need a candle and a pinwheel

We light the candle and we put the pinwheel above the candle. The fire from the candle warms the air. Hot air goes up and moves the blades of the pinwheel.

Air Expansion

Tools: a balloon, two glasses, hot and cold water

At first pour a glass of cold water and a glass of hot water. Put the balloon into the glasses. The balloon in the glass of hot water inflates. The balloon in the glass with cold water deflates. The balloon inflates in hot water because the motion of particles is accelerated due to the heat, and the particles scatter. The balloon deflates in cold water because the motion of particles is slowed down.

Ice cube and pillow

We will need:
a pillow
few ice cubes
2 glasses

I’ll take ice cubes and I put them into the glasses. Now, I’ll give the pillow on the first glass with ice cubes.
We have to wait for 2 minutes.
After 2 minutes we can see how the ice cubes under the pillow melt down as slowly as ice cubes without a pillow. Why? The pillow doesn't heat, pillow keeps a body temperature. So, the pillow can't heat up ice cubes.

Ice hook

I will try to lift up the ice with a toothpick. You can see it does not work. So I sprinkle salt on the ice. I wait for 5 seconds. Now it works because salt lowers the temperature so the toothpick sticks in the ice.

Making ice cream

First I pour cream on the bottom of a glass and add some vanilla sugar to it. Second I take a tiny cup, and I fill it with snow. Then I measure the temperature of the snow. I pour a lot of salt there, I mix the snowy mixture, and I measure the temperature again. The temperature is falling. When the temperature is around minus 12 degrees Celsius, I put the glass with cream and sugar into it. Third I stir the cream to make it smooth till it´s frozen, and I taste it.

Strong Air

Aids: a stick or a ruler, a big piece of newspaper Lay a ruler on a table.

Hit the ruler. The ruler flies away without breaking. Again, lay the ruler on the table and put a piece of newspaper on it so that there is no air under the newspaper. Flatten the piece of newspaper carefully. Quickly hit the ruler again. The ruler is broken.

The air above the piece of newspaper pushes it down with a big force. The ruler isn´t strong enough to lift the piece of paper. When you hit the ruler slowly, there is enough time for some air to flow under the piece of paper and to balance the air pressure under and above the paper.

Air in your lungs

For my experiment we need: a big plastic bottle, a big box and a hose.

Fill the bottle with water, close the neck of the bottle with your finger and put the bottle upside down into the box with water. Then push the hose into the bottle and blow into the hose as long as you are able without aspiration. Now you can see how much air you have in your lungs.

Balloon in a plastic bottle

I will try to inflate a balloon in a plastic bottle.
You see it does not work.
There is a way to make it work. Just make a hole in the bottle.
Now it works because the air from the bottle can escape, and it lets the air from your mouth go into the balloon.

Hairdryer and balloon

We need: a hairdryer, an inflatable balloon, a tube Drop the balloon in the stream of air from the hairdryer. The balloon will start flying. The reason the balloon stays in the moving stream of air has to do with Bernoulli's Principle. Bernoulli's Principle says that pressure decreases inside a stream of flowing air. When the balloon begins to move out of this low pressure stream, the higher pressure of the air in the room pushes it back into the moving stream.

Air and water

Can you blow up a balloon without blowing? You will need: a plastic bottle, an inflatable balloon, a knife, scissors, a container with water Procedure: Cut out the bottom of the bottle. Pull the inflatable balloon on the neck of the bottle. Then dip the bottle vertically into water. Explanation: Water penetrates into the bottle because of the snipped bottom. Air has lower density, so it is always above the water. The water pushes the air into the balloon. Try, on the contrary, to depress the balloon into the bottle. Air and water do not mix together. Air is always on top.

Jumping coin

Expansion of gasses We need a bottle and a coin. Put the bottle in a fridge to cool. Rub soap and pour water on the neck of the bottle a little bit. Put the coin on the neck of the bottle to cover it. Put your hands on the bottle, hold it fast and think hard about making the coin jump. In a while, it works! Your hands warm the bottle, the bottle warms the air inside, and warm air wants to escape. When the pressure of the air is great enough, the coin jumps.

Cup hanger

You need a balloon and two cups. Blow the balloon up a little bit. Then place the cups to the balloon and continue blowing. When the balloon is big enough, drop the cups. The cups are stuck to the balloon. While blowing the balloon up, the air inside the cup was pushed away a little bit. The air pressure outside the balloon pushes the cup to the balloon.

Obedient balloon

For my experiment we need: a bottle, a kettle of hot water, a balloon, cold water to cool the bottle down

Close the neck of an empty bottle with a rubber balloon and then put the bottle into the kettle of hot water. The balloon is gradually inflated. The heated air in the bottle expands and the growing pressure causes the balloon on the neck of the bottle to inflate. Then cool the bottle, reducing the temperature of the air inside the bottle. Colder air has lower pressure. External atmospheric pressure pushes the balloon inside the bottle.