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"RATTLEBACK"
"spin bar"
Your young child must correctly identify the shape of each block and then orient it correctly to fit through one of the holes in the bench
"wobble stone" (or "wobblestone") and by the product names "ARK"
complete instructions and science learning guide
Rattleback - Simply Incredible - Easy to Use...Very Hard to Explain Colour:Orange "RATTLEBACK"A rattleback is a semi ellipsoidal top which will rotate on its axis in a preferred direction. If spun in the opposite direction, it becomes unstable, "rattles", stops and reverses its spin to the preferred direction! This spin reversal appears to violate the law of the conservation of angular momentum. Moreover, for most rattlebacks (including the one above) the motion will happen when the rattleback is spun in one direction, but not when spun in the
