In this science project, you will use food dyes to follow the path of water through a carnation. All plants, even those living in deserts, need water to survive. Plants use water to keep their roots, stems, leaves, and flowers healthy and to prevent them from drying out and wilting. The water is also used to carry dissolved nutrients throughout the plant.
Published: August 17th, 2008
The goal of this project is to build a sensor for measuring magnetic field strength and to use it for measuring the strength of different types of magnets.
Published: August 15th, 2008
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 22nd, 2008
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 22nd, 2008
In this section we will show you how to make a powerful solar concentrator that can cook four or five hotdogs in minutes.
Published: July 22nd, 2008
At either end of the rainbow there is light we can not see. Below the red end is near infrared light, shorter in wavelength than the infrared we feel as heat. Above the violet end of the rainbow is near ultraviolet, longer in wavelength than the ultraviolet light that causes sunburn.
Published: July 22nd, 2008
It sounds like the perfect terrorist weapon, but it is a toy that teaches the principles of electrochemistry. It is also a high-tech squirt gun. The Plastic Hydrogen Bomb uses electricity to break apart water molecules into hydrogen and oxygen. Then it uses a spark of electricity to explosively recombine the gases into high pressure steam, which propels a stream of water high into the air.
Published: July 22nd, 2008
A solar cell is a device for converting energy from the sun into electricity. The high-efficiency solar cells you can buy at Radio Shack and other stores are made from highly processed silicon, and require huge factories, high temperatures, vacuum equipment, and lots of money.
Published: July 22nd, 2008
I made a more portable version of the solar cell in a flat panel form. I used the clear plastic top from a plastic CD jewel case as the window, and lots of silicone rubber glue to both attach the pieces together and to insulate them from each other.
Published: July 22nd, 2008
A fuel cell is a device that converts a fuel such as hydrogen, alcohol, gasoline, or methane into electricity directly. A hydrogen fuel cell produces electricity without any pollution, since pure water is the only byproduct.
Published: July 22nd, 2008
In this section we will describe 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 (over a campfire), it can still start fires, and should be used only by those you would trust with a box of matches.
Published: July 6th, 2008
You have probably seen the beautiful rainbow colors caused by a tiny bit of oil floating in a puddle of water. 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 6th, 2008
Make sure the transistor radio is turned off, and the laser is on. Plug the earphone jack of the laser into the earphone socket of the radio.
Published: July 6th, 2008
In this section you will see just how easy it is to take pictures that show realistic three dimensional (3D) images. The pictures can be viewed in three ways - by crossing your eyes, by focussing you eyes at infinity (called the parallel method because the two lines of sight are parallel), and with an inexpensive (or homemade) 3D viewer.
Published: July 6th, 2008
How would you like to talk over a laser beam? In about 15 minutes you can set up your own laser communication system, using cheap laser pen pointers and a few parts from Radio Shack.
Published: July 6th, 2008
This heat engine is very simple. We suspend a small piece of magnetic material at the end of a pendulum. A large magnet is placed near the pendulum, so that the small piece of material sticks to the large magnet.
Published: July 6th, 2008
You could make your own barometers and thermometers, and not worry about calling in a hazardous materials team to clean up after any accidents. You could simply wipe up the mess with a paper towel.
Published: July 5th, 2008
In the first century AD, the mathematician Hero of Alexandria described a device called the aeolipile, in which steam was conducted through pipes from a boiler to a sphere which had two jets from which the steam could escape.
Published: July 5th, 2008
The boat is a plastic bottle, cut in half lengthwise. I used a soft plastic bottle that contact lens saline solution comes in. It is made of white High Density Polyethylene (HDPE), and is very easy to cut using an Xacto knife or other sharp utility knife.
Published: July 5th, 2008
There is a fascination about rockets that delights children and adults alike. The arc of smoke, the idea of flight, and the fun of action at a distance combine to make rockets a wonderful toy. To these pleasures we will add the forbidden glee of playing with matches, and the satisfaction of learning how something magical actually works. Unlike most of the rest of this book, this really is rocket science.
Published: July 5th, 2008