An eddy in a bottle

In order to make our experiment we needed two plastic bottles of 1´5 liters.

In the first place, we perforated a hole of 1 cm in the corks of the two bottles. Soon we filled one of the bottles with water until approximately three fourth parts and if united the two bottles by the corks. In order to unite the two bottles insulating tape can be used. Is very important a good union between the bottle.

When the bottle with water is on the empty bottle it is observed that the water does not fall easily to the inferior bottle, but if we give a circular movement to the superior bottle is generated an eddy and the water falls easily.

When placing the bottle in the superior part, water does not fall by the little compressibility of the air locked up in the inferior bottle that does not leave space to the water that falls. When the eddy is generated when moving the superior bottle, it is put in communication the air that is in both bottles and the water of the superior bottle falls easily in to the inferior bottle.

Colegio Sagrado Corazón (Esclavas)
Sevilla (Spain)

Tin´s race

In order to make this experiment you need the following materials:

1. An empty softdrink can.
2. A baloon. If we don' have, we can use expanded polystyrene (white cork)

In order to continue with our experiment we make the following procedure:
1. Blow up the baloon.
2. Rub the baloon against your hair or a wool article (for example a scarf).
3. Put the softdrink can knocked down on a table and we approach the baloon. After doing this, we can check that the softdrink can move!

Explanation:
This happens because when rubbing the baloon electricity loads. The attractive electrical forces between the loads or different signs of the baloon and the softdrink can make the tin rotates.

Colegio Sagrado Corazón (Esclavas)

Sevilla (Spain)