PHYSICS WITH BALLOONS

El pasado viernes 10 de marzo tuvo lugar una edición más de la JORNADA BILINGÜE compartida con el IES de San Clemente. En esta ocasión, los alumnos de 2º E.S.O. de forma voluntaria colaboraron conmigo en la realización de un taller, all in English, basado en la demostración de leyes físicas y aplicaciones de éstas utilizando globos.
Se realizaron un total de 10 experimentos, cada uno explicado por un alumno al resto del auditorio. Como no podía ser de otra manera, los alumnos arrancaron los aplausos de los asistentes en todos los casos.
Os dejo una reseña de los experimentos realizados con la redacción en inglés y una galería con las fotos. Lo pasamos genial, ¿verdad chicos?

1. IS IT EASY TO BLOW A BALLOON?

·       You want to blow a balloon inside a bottle.

·       Try...

·       What has happened?

·       Is it possible?

·       No, it isn’t

·       But....I can

·       If you make a small hole in the bottle, the air can go outside and the balloon can be blown inside.

2. BALLOON BROCHETTE

·       Blow a balloon and knot it.

·       You want to go through the balloon with this brochette.

·       Is it possible?

·       Try...

·       But...I can

·       What has happened?

·       The balloon doesn’t explode because the spike is introduced where the plastic is not very tense.

·       The air doesn’t escape from the inside of the balloon.

·       If we remove the brochette, the balloon will deflate slowly.

3. HIDING BALLOON

·       Blow a small balloon.

·       Put ten matches lit into a glass bottle.

·       Wait a little and place the balloon on top of the bottle neck.

·       What has happened?

·       The balloon passes through the bottle after the combustion of matches.

·       Carbon dioxide and water vapour can get the air out of the bottle.

·       A vacuum is created which causes the suction of the balloon.

4. MAGIC BELL

·       This is a vacuum bell.

·       When you remove the air that exists inside, a vacuum is generated and the bell sticks to the base.

·       Atmospheric pressure keeps the bell stuck to its base.

·       Place two little balloons inside the vacuum bell.

·       Eliminate the air with the hand pump.

·       What has happened?

·       The balloon increases its size.

·       This is a demonstration of Boyle’s Law.

·       A decrease in pressure implies an increase in volume.

·       This can be made with sweets too.

·       What do you think will happen to the sweets?

5. A BALLOON THAT DOES NOT EXPLODE.

·       Blow two balloons, one with air and one with water.

·       If you approach the balloon full of air to the flame explodes immediately.

·       Now, I need a volunteer.

·       If you approach the balloon full of water to the flame we can see that it does not explode.

·       What has happened?

·       The temperature of the balloon with water increases but the water absorbs a lot of energy and does not let the temperature rise more than 100ºC (one hundred degrees centigrade).

6. THE THIRSTY BALLOON

·       Blow a balloon.

·       Rub the balloon with head hair.

·       Hairs are repulsed because they acquire the same electrical charge.

·       Balloon attracts hairs because they have different electrical charge.

·       Approach the balloon charged to a thin stream of water.

·       The balloon attracts water because they have different electrical charges.

7. CAN RACE

·       Blow the balloon.

·       Rub the balloon against the hair.

·       Place the can lying on a table and approach the balloon.

·       The can moves.

·       What has happened?

·       The balloon is charged with electricity.

·       The can rotate due to attractive electrical forces.

·       Do we make a race?

8. FAQUIR BALLOON

·       Blow the balloon.

·       I need glasses to protect my eyes.

·       Push the balloon against some 20 tacks.

·       What has happened?

·       It does not explode.

·       The force is distributed over all the tacks and there was not enough pressure so that they could explode the balloon.

·       Push the balloon against a single tack.

·       What has happened?

·       The balloon explodes.

·       The force is concentrated at a very small point and the pressure causes the tack traverse the balloon and it explodes.

9. THE DESCARTES TOY

·       Fill a bottle of water.

·       Introduce a blister with a little water inverted.

·       Place a balloon on the neck of the bottle

·       Press the balloon.

·       What has happened?

·       The blister drops because it weighs more as more water enters when we press the balloon.

·       This is a demonstration of the Pascal’s Principle.

·       Submarines and fish use this principle when they want to submerge or rise to the surface.

10. THE KILLER ORANGE

·       Blow a balloon.

·       Take an orange, dry it and peel it.

·       Break a piece of peeling next to the balloon.

·       What has happened?

·       In the orange peeling there are essential oils (limonene) which are able to explode the balloon.

·       These essential oils are used in pastry or perfumery.