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More about this programme: http://www.bbc.co.uk/programmes/b013gp4t Performing live in Edinburgh, The Boy flies a plane, and orchestrates an elaborate disco dance.

El Vendedor de humo es un cortometraje de Animación realizado íntegramente por los alumnos de www.PrimerFrame.com

CHELO ANDREU - ANIMACIÓN/ MODELADO PJ Y PROPS
ÁLEX PUIG - ANIMACIÓN / MODELADO DE PJ / RIGGING
YOLANDA ÁGUILA - ILUMINACIÓN / MODELADO DE PROPS Y ESCENARIOS
FABIO CARMONA - ANIMACIÓN / MODELADO DE PJ Y PROPS / RIGGING
BORJA LÓPEZ-GALIANO - DISEÑO, MODELADO, TEXTURIZADO Y SHADERS DE PJ Y PROPS / ANIMACIÓN
JORGE MUÑOZ - ILUMINACIÓN /MODELADO PJ Y PROPS / ANIMACIÓN
ALEJANDRO MONREAL - FX / ANIMACIÓN / MODELADO PROPS / GUIÓN
JHONY CHAVESTA - ILUMINACIÓN / MODELADO DE PJ Y ESCENARIOS
JORDI AMPOSTA - ILUMINACIÓN / MODELADO DE PJ / MODELADO PROPS
MÓNICA RÍOS - ANIMACIÓN / DISEÑO Y MODELADO DE PJ Y PROPS
MAJO SILVA - ILUMINACIÓN / MODELADO DE PROPS Y ESCENARIOS / LAYOUT
MIGUEL ORREGO - ILUMINACIÓN / DISEÑO Y MODELADO DE PJ / RIGGING
MARÍA BARBADILLO - FX / ANIMACIÓN/ MODELADO DE PROPS / LAYOUT / GUION
MARTA RODRÍGUEZ - ANIMACIÓN / PRODUCCIÓN / MODELADO PJ/ DISEÑO Y MODELADO PROPS/ GUION
JUAN MORO - MODELADO Y TEXTURIZADO PROPS Y ESCENARIOS / RIGGING /EDICIÓN / LAYOUT
DAVID QUEROL - ANIMACIÓN / MODELADO PROPS Y ESCENARIOS / LAYOUT
SANTI BONO - FX/ MODELADO PROPS Y ESCENARIOS / LAYOUT
LAURA PORCAR - ANIMACIÓN / COMPO / LAYOUT YUI GÓMEZ - ANIMACIÓN / MODELADO DE PJ
BELÉN MARMANEU - ANIMACIÓN / MODELADO DE PJ
ANDRÉS SERRANO - MODELADO DE PROPS
JAIME MAESTRO - DIRECTOR
CARLOS ESCUTIA - PRODUCTOR
AITOR HERRERO - DIRECTOR DE ARTE
EDUARDO OLIDEN - SUPERVISOR ANIMACIÓN
ANA AMAT - SUPERVISIÓN ILUMINACIÓN
RAÚL COLOMER - SUPERVISIÓN DE FX
RUBÉN SOLER - SUPERVISIÓN GUIÓN
TWELVE DOLLS (Alex Ferrer, Alex Visiedo y Pau Paredes) - MUSICA Y SONIDOS
JUAN ANDRES TRACHINER - SONORIZACIÓN

What forces (i.e. pushes or pulls) are acting on you right now? Most people can identify the gravitational force down, but there must be something else otherwise you would accelerate down towards the center of the Earth. The other main force on you is called the normal force. It is a force perpendicular to the surface that supports you, like the ground or the seat of your chair. You compress this surface and it acts like a spring, pushing you up.

There is a gravitational force of attraction between the Earth and the moon, but is it mutual? That is, are the forces on the Earth and the moon equal? Most people would say no, the Earth exerts a greater force of attraction because it is larger and has more mass. This is a situation in which Newton's Third Law is relevant. Newton's Third Law says that for every force, there is an equal and opposite reaction force. So the force the Earth exerts on the moon must be exactly equal and opposite the force the moon exerts on the Earth. But how can that be - that the same size force keeps the moon orbiting, but barely affects the Earth? The answer is inertia - the tendency for all objects with mass to maintain their state of motion. Since the Earth has much more mass than the moon, it has greater inertia and therefore experiences much less acceleration for the same amount of force.

How do our eyes scan across a landscape? Contrary to popular belief, they don't scan smoothly across a scene, they observe a series of images. The eye is capable of panning smoothly however. If something moves in your field of view, your eyes track it smoothly. This has an important effect on our perception of motion. It makes it more difficult to see when objects are accelerating since the eye tracks all motion quite smoothly.

In Sydney, ice melts because it is warm out in the middle of the day (even in winter). This creates a layer of water on top that certainly makes it slippery. But should it be slippery at night or in a cold northern climate where the air temperature is below zero? Yes, because the pressure your skates apply to the ice actually lowers its melting point allowing you to glide along a thin layer of water.

Animation in this video is courtesy of VisChem (TM), Copyright 1995, Roy Tasker

For a more complete picture of the mechanisms involved in making ice slippery, check out this great article: http://lptms.u-psud.fr/membres..../trizac/Ens/L3FIP/Ic

Yes, I have made a similar vid before. This is the Australian TV version for the ABC show Catalyst http://www.abc.net.au/catalyst/
Misconceptions About Temperature http://www.youtube.com/watch?v=vqDbMEdLiCs
The Mysterious Falling Slinky http://www.youtube.com/watch?v=mAA613hqqZ0
Why Are Astronauts Weightless? http://www.youtube.com/watch?v=iQOHRKKNNLQ

And for those of you wanting a more General Relativity based explanation. Don't worry, it's coming.

What passes through a block of ice more quickly, copper wire or fishing line?

If you've seen footage from the International Space Station or any of the space shuttle missions, you know that astronauts float around as they orbit the Earth. Why is that? Is it because the gravitational force on them is zero in space? (Or nearly zero?) The truth is that the strength of the gravitational attraction is only slightly less than it is on Earth's surface. So how are they able to float? Well, they aren't floating - they're falling, along with the space station. They don't crash into the Earth because they have a huge orbital velocity. So as they accelerate towards the Earth, the Earth curves away beneath them and they never get any closer. Since the astronauts have the same acceleration as the space station, they feel weightless. It's like being in a free-falling elevator (without the disastrous landing).

Director of Photography: Stefan Smith
Camera Assistant: Raa Perajeev
Boom Operator: Maha Sivalingam

Production Coordinator: Adrian Tan
Production Assistants: James Peniata, Pratheep Ramachandran

ZoggFromBetelgeuse's solution: http://www.youtube.com/watch?v=pwl-rBVbWAY
This is a preliminary solution to the spinning disk trick based on the commonly cited tippe top explanation. I have my doubts that it tells the whole story because the disk seems to tilt, so the argument about constant angular velocity is in doubt. I wonder if the weight of the disk plays a more important role in making it flip. Plus, I think the disk appears to roll without slipping while the lighter side is moving down. This violates one of the assumptions of the tippe top explanation. So why am I publishing this now? I feel bad it has been two weeks and I haven't posted the answer yet so let's consider this a starting point for a work in progress...

When sunlight shines through a small hole, it casts a circular image on the wall regardless of the shape of the hole. The size of the hole also doesn't affect the size of the image.
This counterintuitive demonstration shows that the hole is acting like a pinhole camera, producing an image of the sun on the wall. Therefore the size and shape of the hole have no effect on the size and shape of the image.

What happens when you decrease the pressure around a liquid? It boils. Water boils at room temperature once the pressure is low enough. What is interesting is that this decreases the temperature of the liquid. The fastest molecules escape, leaving the slower ones behind.
Using this trick with liquid nitrogen, it is possible to create solid nitrogen at a temperature of -210C. We then poured the solid and liquid nitrogen mixture onto a tray of water. The surface of the water became so cold that CO2 solidified out of the atmosphere on its surface. Then, since CO2 does not pass through the liquid phase at atmospheric pressure, it was propelled on the water surface by jets of gas as it sublimed.
Huge thanks to the Palais de la Decouverte.
Music by Kevin MacLeod of Incompetech.com (Mirage)

How long is the coastline of Australia? One estimate is that it's about 12,500 km long. However the CIA world factbook puts the figure at more than double this, at over 25,700 km. How can there exist such different estimates for the same length of coastline? Well this is called the coastline paradox. Your estimate of how long the coastline is depends on the length of your measuring stick - the shorter the measuring stick the more detail you can capture and therefore the longer the coastline will be.

If the Earth were the size of a basketball and the moon a tennis ball, how far apart would they be? Diagrams that are not to scale make us think that they're closer than they really are.

There seems to be confusion about what radiation is and where it comes from. Many people believe it is the radiation that comes directly from nuclear power plants that poses a threat to public safety. In fact it is the radioactive atoms, which can escape in the event of an explosion, that pose a safety risk. They can be scattered by the wind over hundreds of kilometres. Then they may be ingested or breathed in. If they release radiation at this point, it is damaging to the body's molecules and cells because the radiation is delivered directly to tissues.

When we touch something that is hot or cold, what are we actually sensing? Is it the temperature of the object, or the rate at which heat flows between the object and our hand?

Whenever an object spins through the air it experiences a 'Magnus Force' due to friction between the air and the object's surface. This force was originally identified while studying the trajectories of cannon balls (though earlier observations of this effect exist). The Magnus force is essential in most ball sports including golf, cricket, tennis, and baseball.

At the end the ball demonstrations were conducted with a 100 mm diam polystyrene ball and the launcher was made by bending a long, thin, aluminum rod and bolting the ends to a block of wood as a handle.

Music was provided by Kevin McLeod (incompetech.com) Scissors and a stock clip from FCP.

Want more awesome HD slow-mo? http://www.youtube.com/watch?v=uiyMuHuCFo4
Slinky not long enough? Click here: http://www.youtube.com/watch?v=JsytnJ_pSf8
How does a slinky fall when extended by its own weight and then released? We discover the surprising answer using a slow motion camera that records 300 frames per second. Answer link: http://www.youtube.com/watch?v=oKb2tCtpvNU

For a great explanation, check out Rhett Allain's analysis here: http://www.wired.com/wiredscie....nce/2011/09/modeling

When pressure is applied to ice, its melting point is reduced so it turns to water. When the pressure is removed, however, it turns back into ice. This process is called 'regelation.' Big thanks to Art of Ice Sculptures www.icesculpture.com.au who donated the beautiful block of ice.

Many videos on YouTube show water freezing almost instantaneously. This video shows you how to replicate the experiment and it explains how the phenomenon works. Molecular illustrations are courtesy of:
PhET Interactive Simulations
University of Colorado
http://phet.colorado.edu.