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Duncan® Yo-yo $4.50

A genuine Duncan® yo-yo that's just as much fun now as it was years ago.

There is a lot of physics found in a yo-yo. Consider the case where you simply release the yo-yo, letting it fall naturally.

Just before you release it all the energy is in the form of gravity. As it falls the gravitational energy is turned into kinetic energy. This energy of motion is the falling of the yo-yo and the yo-yo's spin as it falls.

Near to the bottom of its path, all of the energy is in the motion of the yo-yo. With no place left to go, the yo-yo pulls on the string so that it is taut. At its nearest point to the gound, all of the energy is in the string pull. Then the string acts a bit like a spring and the yo-yo is jerked upwards.

On its return trip the yo-yo moves upward, spinning in the opposite direction as it did going down. Since energy is lost to friction and heat, the yo-yo does not have enough energy to make it back to your hand.

That's why one throws a yo-yo. If you start it with enough extra energy from your throw, the yo-yo will make the round trip without any more help. If your initial throw does not add enough energy to insure a round trip, you can give the yo-yo a gentle tug as it reaches its lowest point. This tug adds to the string recoil assisting in the yo-yo's return to your hand.

As this is a 'virtual' store, it is hard to see how the yo-yo works. That realization led us to create a virtual try before you buy!

Click to see a sample of the color choices. You may indicate your style preference (regular, butterfly or an assortment) in the comment as you complete the ordering process.

Gift wrap orders: input salutation in the comment section at the end of the ordering process.

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