Also known as fidget spinner, O hand spinner (“hand spinner”) is a toy that can be rotated between your fingers. Usually made of plastic or metal, the device is formed by a central bearing where three types of propellers are coupled.
hand spinner model
what is the hand spinner?
The use of the device can help people who suffer mainly from anxiety, stress and attention deficit hyperactivity disorder. spin one hand spinner it also helps to combat minor addictions, such as biting nails or putting small objects in the mouth, such as pen caps. The toy can even be used to increase the concentration of autistic children and assist in the development of motor skills.
The use of equipment such as the hand spinner makes the tension in the execution of some activity to be reduced, which allows its use in relaxation techniques.
make your own hand spinner!
Many videos on the internet teach you how to build your own hand spinner. The materials used are basically pipes PVC, bearings and glue. The following video shows you a step-by-step way to build your own spinning toy.
physical principles
When turning a hand spinner, there are at least three physical principles involved:
1. low friction
A good hand spinner easily surpasses one minute of uninterrupted rotation. This is only possible thanks to the bass friction existing between the components of the bearings that make up the device. The lower the friction, the lesser the performance of dissipative forces and, in this way, the device will rotate for a long period.
2. gyroscopic effect
When the hand spinner is rotated quickly, you can see the appearance of a "force" that prevents its inclination during the movement. This happens because of the gyroscopic effect, in which a rotating body always tends to keep its axis pointed in the same direction. It is also because of this effect that it is easier for us to maintain our balance on a moving bicycle than on a stationary bicycle, for example.
Motorbike riders face the gyroscopic effect during turns *
In motorcycle speed competitions, riders face the gyroscopic effect when executing the turns. As a result, the transmission axles of racing motorcycles rotate in the opposite direction to the wheel in order to reduce the action of the gyroscopic effect and facilitate the execution of curves.
3. Strobe Effect
In the video above with instructions on how to make a hand spinner, when observing the rotation of the home appliance in an instant of 4 minutes and 50 seconds, it can be seen that, apparently, the device rotates in a direction opposite to the initial direction. This same effect can be observed in car wheels, when they appear to rotate in the opposite direction to the vehicle's movement. These optical illusions occur because of a phenomenon called the stroboscopic effect.
Through images in videos or even while observing the hand spinner rotating under a flashing light, we can notice the strobe effect. With the rapid rotation of the device, our eyes always capture images at different points. If the images are captured before any luminous point completes a revolution, the sensation arises that the observed point rotates in the opposite direction to the real one.
* Image credits: Dan74 / Shutterstock
By Joab Silas
Graduated in Physics
Source: Brazil School - https://brasilescola.uol.com.br/fisica/hand-spinner-fisica.htm
