Thursday, October 30, 2014

The supper balloon - fireproof balloon

Ok, now I'm gonna tell you how to build a cool science experiment. It's called the balloon that doesn't pop, or if you would like a more attractive name you may call it the super balloon. Take a regular balloon, blow it up and put it over a candle's flame. Can you wonder what's gonna happen? yes... it will pop. But look at this balloon, it's over the candle's flame and doesn't pop, what is the secret behind this super balloon? The secret is..... the balloon is full of water. But how water prevent the balloon to pop? The water has a high specific heat, in other words it need to absorb a lot of heat to increase its temperature. Beside that, the water is a great heat conductor, in this case mainly by convection. So the balloon doesn't reach the temperature enough to melt its polymer and pop.
Wednesday, September 15, 2010

Slow Motion ligthning

How does a lightning form? And how does it behave?

These two questions are hard to answer because the lightning happens so fast that we see just a blinding light coming from the sky followed by a deafening thunder.
What, in ancient times, was considered divine powers, today is explained and detailed observed with help of science.
This video shows a slow motion lighting behavior.
We can see the three kinds of lightning: cloud to the ground, ground to the cloud and cloud to cloud.
Is also possible to see how the discharge follows the ionized air of the previous discharge.

Friday, August 13, 2010

Triboelectricity - Children playing on a Plastic slide

When two materials are rubbed a kind of effect appears, they become charged. The polarity (what material will become positive and what will become negative) is given by the triboelectric series.
Usually, physics teachers use a pipe and a cat or rabbit hide to demonstrate this effect. This video shows how a children playing on a plastic slide can generate static electricity.
Both, children and slide become charged and that can be noted because the children’s hairs stand on end.
Friday, March 12, 2010

The best science tricks for parties, at least a geek party!

This video shows simple science tricks that can be used to amuse friends in a party, play with children or even in a science fair. I wish you enjoy it.
Thursday, February 18, 2010

Steve Spangler teaches how to make square bubbles

Square bubbles sounds impossible, ours brains connect the word bubble with the spherical shape. However this video shows how to produce square bubbles using a science trick.
Tuesday, February 2, 2010

Flutter Effect - Dynamic Aeroelasticity

Flutter Effect is a self-feeding mechanism in which aerodynamic forces on a object (This case an airplane wing) are coupled with the natural mode of vibration of this object to produce a periodic and, sometimes, destructive motion.
Thursday, January 28, 2010

Lets pump...pumpkins

This video shows a pumpkins cannon. It uses compressed air to accelerates the pumpkins through out a long pipe. As bigger the pipe, more time the pumpkin is accelerated, so higher is the inicial velocity. At a 45 degress angle the pumpkin reach the maximum horizontal distance.

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