Showing posts with label Physics. Show all posts
Showing posts with label Physics. Show all posts
Thursday, July 23, 2009

Make at home one Wilson's machine

"An early electrostatic influence machine, invented by Wilson in 1804. A ball electroscope observes the output voltage."
From: youtube description video

Music from a straw and a chicken in a cup

Science bob explain quickly how to produce sounds from a straw and how to make a chicken voice using a plastic glass.

Is possible to boil water inside a balloon?
Find out how the materials absorb heat and the relation between heat and temperature for different materials.

Simple way to build an electrical motor
Instead of these materials you can use a simple magnet from speakers, paper clips and adhesive type to build your own electrical motor.

Different kind of electrical engine
This video shows a different kind of electrical engine, it uses two coils as electrical magnets to attract, alternately, a piece of iron and generates movement.

Infra red images of everyday life 2
Water and ice when looked at infra red camera can help us to understand how light and heat are related.

Infra red images of everyday life
Infra red light can be thought of as “heat”
The warmer something is, the more brightly it glows in the infrared.
Apiece of glass may be bright, but it is cool, so it will appear black in the infra red camera.
Even though a person may stand in shadows her body heat shines in the infrared.

What makes the sky blue?

Play baseball with molecules and learn what makes the sky blue or sometimes red!

Marshmallows in a vacuum chamber

Marshmallows contains air inside, the vacuum will reduce the inner pressure and make the air inside the marshmallows expand, thus the marshmallows grow up.

Fishing ice cubes

Using science principles this video shows how to fish an ice cube.

conducting glass

Click here to see how a piece of glass can become a electrical conductor.

"A small glass tube, held by copper wire, is placed in series with a light bulb. The glass acts as an insulator at room temperature, meaning the current cannot flow between the copper wires. This leaves an open circuit and the light bulb does not light up. Touching a conductor across the copper wires (with a metal screwdriver for instance) does complete the circuit because it allows current to flow.

However, when glass is sufficiently heated by a torch it becomes an ionic conductor. Ionic bonds in the glass are broken, allowing the charge carrying ions to move freely. Thus, when the glass is melted the current can flow, which closes the circuit and lights the bulb.
See the original video on MIT TechTV -"
From: MIT youtube channel
Wednesday, July 22, 2009
Tuesday, July 21, 2009

Egg in a Bottle Science Trick

Follow the instructions and learn the classic and fantastic science trick: “Egg in a Bottle"
The hot air inside the bottle cools down reducing the inner pressure, thus the atmospheric pressure will push the egg.
Saturday, July 18, 2009

Paul Hewitt shows how to produce colored shadows

In this video we can see the three primary colors come together and forming white light. Paul Hewitt also shows how to produce colored shadows, that is incredible and fun! Try yourself in home; you’ll need just three lights: red, green and blue.
The TV screens uses the same principle, with this three colors mixed together is possible make any other color, will depends just of intensity of each one.
Sunday, July 12, 2009

Science Experiments: Magic soap bubbles

Baking soda and vinegar are very useful in science experiments, here we have another example in which this materials are used to amaze the people!
Put some vinegar in a aquarium, latter put some baking soda. The result of reaction is sodium acetate and carbon dioxide.
The CO2 is more dense than the air, so a soap bubble will float on it as a boat float on water. The buoyancy force is equal the weight of the bubble, thus we have the equilibrium and the bubble remains on interface CO2 / Air

How many pins is possible to put in a glass completely full of water?

As you can see in the video above, the answer is a lot! The is possible thanks a property called surface tension. The liquid’s surface molecules attract each other forming drops or the spherical layer over the glass formed by the volume occupied by pins.
This property of liquids allows small insects literally walk over the water without sink!
See more on Wikipedia

Slow motion rubber band trick

Put a rubber band in front of a TV screen to see it vibrating in a slow motion. Actually the vibration remain the same but we have the sensation that it slow down. This phenomenon is possible just because the frequency of rubber band's vibration is near the vertical frequency of screen.
The TV screen works as a stroboscopic light and it will not works in front of LCD screen.

Build a little hot air balloon: the tea bag experiment

Using a simple tea bag is possible make a little hot air balloon, see the video instructions.
The fire heat the air inside the balloon, hot air is less dense than cold air, result: a buoyancy force greater than the weight will make the balloon fly.

Classic Science Experiments: Egg in a Bottle

Classic Science Experiments: Egg in a Bottle
You will need: a egg, an empty milk bottle and some matches

The match warm the air inside the bottle
the air become less dense and go out. Since the egg close the bottle, the air inside cool and the inner pressure reduce. Thus the atmosphere pressure push the egg.

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