| Tornado Tube Kit Includes one tornado tube connector and the 125 page book, "Taming the Tornado Tube," by Steve Spangler. The scientific principles behind vortexes, tornados and hurricanes are fully explained, followed by 50 weird and wacky experiments using this ingenious toy. PY15 $14.40  | ||||||
| Radiometer This fascinating apparatus actually turns light into motion; the vanes rotate inside the glass bulb when exposed to light. The brighter the light, the faster they spin! PY10 $13.90 | ||||||
| Hand Boiler Watch the heat of your hand boil the fluid and force it into the upper bulb. Made of glass, not recommended for children under 7. PY09 $5.95 | ||||||
| Drinking Duck Dip the head in a glass of water and stand the bird upright to start the dipping. Explanation included! PY12 $6.70 | ||||||
| Happy / Sad Balls The set consists of two 1" rubber balls, outwardly identical but with very different mechanical properties. The happy ball will bounce energetically, while the sad ball is completely flat. Spin them, freeze them, roll them down an incline plane...can you predict which will bounce and which will not? Comes with instructions, including a short history of rubber processing. | ||||||
| Item | Description | Price | |
| PY26 | Happy / Sad Ball (1 pair) | $8.20 | |
| PY26S | Happy / Sad Ball (classroom set, 15 pairs) | $99.95 | |
| Compound Bar Demonstrates unequal expansion in different metals on heating. Consists of a laminated strip of two different metals which will bend dramatically on heating, due to differences in linear expansion. PY03 $6.15 | ||||||
| Law of Motion Demonstrator If a rifle bullet is fired horizontally and another is dropped vertically from the same height at the same time, which will hit the ground first? Demonstrate Newton’s second law of motion with this simple spring-loaded apparatus. One ball is projected horizontally while the other is released vertically at the same time. PY19 $21.75 | ||||||
| Ball & Ring Shows expansion of metal when heated. Brass ball fits through brass ring at same temperature but will not fit if ball is heated. Wooden handles. PY02 $9.90 | ||||||
| Heat Conductometer Aluminum, brass, copper, nickel and steel rods, each 95mm long, demonstrate rate of heat conduction in each different metal. Cavity in end of each rod holds paraffin (included). PY01 $9.70 | ||||||
