Monday, August 31, 2009

Make a rainbow over your hands



This book uses the same principle of a flip book to give us the visual sensation of a rainbow.
The way in which a real rainbow is formed is very different. In the sky the colors are formed by the decomposition of white light inside of little particles of water that make the clouds.
Here a strep with some colors of rainbow is placed in each page of the book, when we flip it the rainbow appears. A phenomena called visual persistence allows that, to see more about visual persistence click here.
Tuesday, August 11, 2009

Leidenfrost Effect: putting the finger inside molten lead


This video show the physical principle that allows put the finger inside a molten lead without burn it.
The humidity of ours skin evaporates and the molten lead do not touch the finger.
The same happens with water drops in contact with a very hot frying pan . They don’t evaporate immediately because a vapor layer protects the drop from the heat.
Saturday, August 8, 2009

Learn how to do a sodium dichromate volcano

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Sodium dichromate is a orange solid. During its decomposition N2 , water and chrome oxide are liberated. The total volume increase in about 30 times. Some chrome oxide dust and the heat liberated make it really seamed with a true volcano.

Thursday, July 23, 2009

The old tablecloth trick by Paul Hewitt


Paul hewitt demos, using humor, inertia and physics pulling a tablecloth out from under a table full of plates and glasses and not moving or breaking anything.

The light bulb history may inspire you


The journey for creation of light bulb is shown on this video.

Collection of experiments using a Van de Graaff generator


"This is a collection of experiments using a Van de Graaff generator.

The generator uses a belt and two rollers to build up a charge in the dome on top. The electrons will jump from the dome to reach a grounded object. Since like charges repel one another, objects placed on top of the dome will become charged and then be repelled.

This is the same machine sometimes used to make someone's hair stand up in classrooms or in science centers."
From: You tube descripion video

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