Tuesday, December 15, 2009

A valley in thirty seconds



"This activity models how tensional forces can cause fractures in rocks, sometimes creating rift valleys" From description of youtube

The earth is a dynamic planet, in ours human life time we barely note that, perhaps just when a volcano erupt or a earthquake destroys a city. Analyzing geological features in rocks we found out pieces of a huge puzzle and then theories are created. To confirm those theories some lab experiments were made. This video shows a qualitative experiment that demonstrates how normal faults are formed in a rifting process.

Chemistry Experiment - How to make a mirror



Mirrors always fascinating the human being, the possibility to look ourselves face to face is a mark in a culture of a people. That’s why these objects were so precious in ancient times and still are for some indigenous tribes.
Nowadays it is used, beside the self admiration, in cameras, telescopes and satellites.
When the man first went to the moon, they left a mirror there, so today using a laser is possible to measure the distance earth moon very accurately.
This videos shows how to make a mirror by using the glucose to reduce a silver complex. The metallic silver is deposited in the flask forming a mirror’s surface.
Saturday, December 12, 2009

Falling Smoke



The smoke inside the bottle falls becouse it is cold. Otherwise it ascend with the warm air as we always see.

Pascal Principles and plastic bottles


Physics demonstration of Pascal principle using plastic bottles
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.

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