By using a pair of polarizing filters and a property of certain materials called birefringence we can photograph the hidden stresses in hard plastics.
Published: May 1st, 2008
A magnetorheological fluid is a liquid that hardens near a magnet, and becomes liquid again when you remove the magnet. They are simple to make in your kitchen after a trip to a sandbox.
Published: May 1st, 2008
Here is how to make your own jet enigne to power your wacky vehicles
Published: May 1st, 2008
A mini-rocket that uses water and carbon dioxide as "fuel". The principle of the rocket is simple; the Newton third law of motion states "for every action there is an equal opposite reaction". The action is the gas produced by the effervescent when is in contact with water. The gas creates pressure and accumulates until the cap pops out. As the cap have no where to go, the plastic can goes up (the opposite reaction) because the gas pushes it.
Published: May 1st, 2008
Here is an easy-to-build homemade thermometer that can be built in about one hour using materials available at home.
Published: May 1st, 2008
How to make a powerful solar concentrator that can cook four or five hotdogs in minutes. The Solar Hotdog Cooker is made out of a thin (1/8 inch thick) plastic mirror that can be found at plastic shops and glass stores.
Published: July 18th, 2007
How to make a marshmallow roaster, powered by the sun. It can be made from readily available materials, and while it is probably a little safer than the traditional method of roasting marshmallows.
Published: July 18th, 2007
A simple toy microscope and a disposable camera can team up to make stunning photographs of very tiny things. You simply focus the microscope carefully by eye as you would normally do. Then you place the camera lens right up against the eyepiece, and snap the picture.
Published: July 18th, 2007
Some cheap computer video cameras have adjustable focus lenses that can focus almost right up to the lens. This allows you to aim the camera straight up, and put a microscope slide on the lens ring, and focus on the slide.
Published: July 18th, 2007
An Electric Fish emits pulses of electricity into the water, with which it locates food, other fish, and potential mates. It is easy to listen in on these electrical signals with simple inexpensive equipment, such as a piezoelectric earphone, or a small amplifier.
Published: July 18th, 2007
In this section we will build a toy called the Polariscope. As you can see from the above photograph, the Polariscope creates patterns of beautiful colors, somewhat like a kaleidoscope, but by an entirely different mechanism.
Published: July 16th, 2007
A spectroscope is a device that lets us find out what things are made of. It works by taking light and splitting it up into its component colors. Different elements make different colors when they glow.
Published: July 16th, 2007
In this project, we are going to capture those colorful patterns on paper, in a permanent form, so you can view them anytime you like, without a messy puddle.
Published: July 16th, 2007
As you turn this little paper sculpture inside-out, it changes colors. First yellow, then blue, then red, then green, and then yellow again. You can keep turning it inside-out, cycling the colors, as long as you like.
Published: July 16th, 2007
It is a powered respirator with a blower and filter I could wear, perhaps around my waist. An additional difficulty was my glasses. When I wore the Pro-Air respirator I found it very difficult to get a pair of goggles to go over my glasses and fit with the respirator on my face.
Published: June 9th, 2007
To determine whether the level of certain chemicals in the tributaries to the Yakima River was different in the rural area of the Umptanum Creek compared to the urban area of the Wenas Creek.
Published: May 28th, 2007
Crystals are not alive, but they can grow. Growing crystals requires a little time and patience. If you have both (plus a few other ingredients), you can grow your own crystal gardens.
Published: May 28th, 2007
The students will create a magnetometer to monitor changes in the Earth\'s magnetic field for signs of magnetic storms.
Published: May 28th, 2007
We talk about the construction of a sidereal pointer. It is an instrument that allows you to localize each celestial object in the night sky, just knowing its coordinates.
Published: May 28th, 2007
Hipparchus, who used an eclipse of the Moon to deduce the precession of the equinoxes, used a total eclipse of the Sun - probably in 129 BC - to estimate how far the Moon was.
Published: May 28th, 2007