
If the question is whether to tie a bunch of these giant weather balloons to a lawn chair, the answer is no. (They burst at about 82,000 feet anyway.) Besides, this is a true weather balloon, with plenty of fun, nonfatal uses. The cream-colored latex balloon is approx 40" dia when flaccid, you should pardon the expression, but has an 8-foot dia when inflated. The neck is 9" long x 1" dia. Scientists, meteorologists, inventors, teachers and the imaginative filmmaker are warned to launch the balloon carefully. The material is delicate and not made to survive brushes with pavement, pine branches, or clumsy physics students.
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94055 8 FT DIAMETER LATEX WEATHER BALLOON |
That's what you get with this tesla coil!! Brand new, commercial item, great for classroom demonstrations and experiments. The 50,000 volt capacity generator radiates high frequency energy through space... enough to light fluorescent tubes two feet away. It uses 115 VAC (60 Hz) with an electro-magnetically operated interrupter buzzer, high voltage capacitors, inductive coil transformer, and a monopolar high frequency transformer generator to do the trick. 11" high, with a 6" sq. x 2" high protective housing for the generator. Includes accessories and instruction booklet with 19 experiments. Pretty amazing. But please, this is not a toy and should be used only under adult supervision.
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70301 50,000 VOLT TESLA COIL Note: This item is not eligible for Expedited Shipping or delivery to Alaska, Hawaii, or the Territories. |
An easy way to light up the kids' eyes! Teach them to wire a simple circuit with our basic components. The knife switch is mounted on a plastic base. The miniature plastic socket holds a standard flashlight bulb with a 14 mm dia screw base. We pack 6 volt and 3 volt round bulbs, or 1.5 volt bell-shaped bulbs, (5) to a package.(Bulbs are rated slightly higher to prevent them from burning out.) Or hook up the black plastic and metal 2" x 4-1/4" telegraph key with brass contacts and (2) terminal posts with nuts. Our blue-plastic holder for (1) "D" battery has a small tab at each end to hook a lead to, and a 1/8" square mounting hole at each corner. You add the mounting surface and the know-how. Actual bulb voltage listed in parenthesis.
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91160 1.5 VOLT BULBS (2.5 V) | |
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91159 3 VOLT BULBS (3.8V) | |
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91158 6 VOLT BULBS (6.3V) | |
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91769 BATTERY HOLDER | |
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38806 KNIFE SWITCH, DOUBLE POLE DOUBLE THROW | |
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38808 KNIFE SWITCH, DOUBLE POLE SINGLE THROW | |
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38805 KNIFE SWITCH, SINGLE POLE SINGLE THROW | |
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38811 SOCKET | |
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91813 TELEGRAPH KEY |
…when you crank up this 13-1/4" tall, hand-cranked Wimshurst generator. They were the toast of the 19th Century, and remained the hottest thing around, electrostatically speaking, until Bobby Van de Graaf came along. This one works like a top, zapping sparks to a fare-thee-well with very little cranking. It's mighty pretty too, in acrylic, white and silver, and will dress up a dull physics or electronics lab.
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93600 STATIC ELECTRICITY WIMSHURST GENERATOR |
Classroom and Science Fair alert: Now you can order an 8-pack of metals and metal alloys for demonstration purposes. Each pack of 1" dia x 1/32" thick discs includes aluminum, bronze, brass, copper, n/silver (w/nickel), m/steel (mild: low carbon), stainless steel, and zinc. Composition of each is stamped on one side of the discs.
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93769 METAL SAMPLES |
You can start with our single aluminum tuning fork, 2-tined and 7-1/2" long. It vibrates at 256 hz, and is labeled "C". Or you can order the set that has (8) forks and a mallet with a rubber-tipped plastic head. The forks are labeled low-C to high-C and come in a fitted, latched wooden box. Unfortunately, C.J., who has perfect pitch, tells us that his pitch is more perfect than most of the tuning forks. He also says you can file the tips, tuning them to an electronic keyboard until they're perfect - and we think there's a certain cachet to telling people you tuned the forks yourself. But they are perfect, if you're using them for things like teaching principles of sound or driving the chihuahua crazy.
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91185 TUNING FORK | |
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91772 TUNING FORKS, SET |
You choose between our 2" square classroom demonstration slides. The diffraction grating slide has 500 lines per mm resolution and a wavelength chart; the linear polarized filter slide has a 1-3/8" x 15/16" window. Nice for classroom and home-schooling use. Made in the USA.
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93902 DIFFRACTION SLIDE | |
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93903 POLARIZED SLIDE |
Newton would have killed for this, but you can have it in your classroom for a song. Our high-quality composition-of-light unit is designed to demonstrate the nature of light wavelengths. A trio of tubes with red, green and blue LEDs inside have converging lenses, in turn mounted in swiveling holders. Sturdy, heavy-duty plastic construction through-out. It's powered by an included 4 "D" cell battery pack (Batteries, not included.). Has individual switches and brightness controls for each color, plus a 6-1/2" x 7-1/2" mounted white screen for display, plus a handy instruction sheet.
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93487 RED, GREEN AND BLUE LED LIGHT DEMONSTRATOR |
The next best thing to lightning bolts! 200,000 volts of electrostatic energy created by our Van de Graaff generator. Measures 6-1/2” diameter by 15” tall, and a newspaper-like set of instructions includes lots of fun experiments. For grade 6 and up. This is not a toy and should be used under adult supervision. A great tool for teaching about electricity. For your convenience, we now have Lightning Belts: replacement belts to drive that overworked generator.
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94250 ASSEMBLED VAN DE GRAAFF GENERATOR | |
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94057 VAN DE GRAAFF BELT |
They might as well learn something while they're trying to outlast you on eating those lima beans. Set the table with educational placemats and they'll be at least a touch smarter after dinner, even if their vegetable intake is low. These laminated, 12" x 17-3/8" mats have full-color fronts, black-and-white backs. Choose the United States Map, Stars & Constellations, the Periodic Table of Elements or The Metric System.
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92515 ELEMENTS PLACEMAT | |
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94354 METRIC SYSTEM PLACEMAT | |
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92514 STARS PLACEMAT | |
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92513 US MAP PLACEMAT |
Good across the occupational spectrum, from visual artists to physics teachers-this full-service color paddle set comes with red, blue, green, cyan, magenta, and yellow gels; (2) diffraction grating gels-(1) at 13.5 lines/inch, double axis, and (1) 500 lines/mm; (2) polarizing filters; and (1) translucent white diffusing filter with 63% transmission. All gels and filters are 2-1/8" x 2-5/8" in cardboard frames 5-7/8" long, and there's a built-in spectral transmission chart for primary and secondary colors. Made in the USA.
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92683 COLOR PADDLE |
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