Tedco Rattle Back (Multicolour)

My husband saw a video of the toy somewhere online, and liked it so much, he had to have it. I found it here on amazon. It does work just like it supposed to - spins freely in one direction, like a run of the mill top, but when spun in opposite direction, it stops and starts spinning backwards. It is quite entertaining, and fun to show friends. It is made of clear plastic - mine is green, the color is quite dark.

Very nice scientific curiosity. They are plastic so don't expect the craftmanship to be exquisite, but they serve the purpose more than well, and they are fun to watch and play with. I played with my 7-year old son for over 30 minutes. It only switches rotation when you spin in one given direction. If you spin in the opposite direction, it will continue that way until it comes to a stop. So based on which way you start it (clockwise or anticlockwise) this piece of plastic will start to wiggle, come to a stop at start rotating (2-3 times) in the opposite direction to which it started, or else just continue spinning in the same direction it started. I told my son I had magic, and could make it rotate in the opposite direction. When he tried doing it, I would just rotate it in the opposite direction and make him think "he did not have the magic". After 20 minutes with the illusion, my mother took pity and spoiled it by letting him in on my secret.

Very cool item! Demonstrates how the earth's counter clockwise rotation effects this very simple gadget. I totally AMAZED my friend with this one! Hehe

its a fun toy and I enjoy playing with it while at work. fits my desk toy criteria. The only negative remark I have is, when it changes direction it stops just after two rotations, I guess its because of the build quality, it looses too much of energy while its rattling.

Cute curiosity. Was a crowd pleaser in a group of geeky friends :-)

I had seen one of these in the office and was very intrigued, so when I placed an order I found one to add to my order. This is a dud, it does spin back eventually, but half the time it's a half rotation and it just stops. The one at the office that someone has actually spins back around and continues to spin a few rotations, it's very cool, the one I have is worthless. I've very disappointed.

This is a wonderful toy that will absolutely dazzle your fellow engineers or scientists. I had a physicist in my office who watched me spin the rattleback and he actually got out of his chair, exclaiming "That's not possible!". He spent the next ten minutes examining this innocuous piece of plastic, looking for the mechanism that would allow it to violate the laws of physics. Needless to say, I get a lot of mileage out of these toys. Please be advised: If you order more than one of these via Amazon, they will stick you with a shipping charge for each item as if each item were being packaged separately (they came in one small box). So the six or eight dollar charge it should have been ended up over $59 for ten small pieces of plastic!

It works!

中学校で生徒に参考として示すために購入しました。興味を引くことができ、購入の目的を果たせそうです。 実験など教育目的での購入ならともかく、ただのおもちゃとしては高すぎると思います。 購入時は色を選ぶことができませんでした。現在はどうなっているか分かりませんが。

Magnification not very useful, but the rattle back effect is clear and dramatic.