Hand Spinner Physics
The Hand Spinner is a toy capable of helping people with attention deficit and works from interesting principles of Physics.
The device is widely used to help people who have attention deficit , hyperactivity, stress , autism and minor addictions, such as nail biting .
Why use Hand spinner?
High levels of stress and attention deficit hyperactivity disorder make some individuals unable to concentrate on a specific activity. The use of devices such as the Hand spinner makes the brain not focus on the environment and is free to focus on a single specific action.
Instead of biting your nails, swinging your legs and biting small objects, for example, you can use the Hand spinner to stay focused on a certain activity. The device can still be used to develop the motor skills of children with autism or with some motor difficulty.
Make your own Hand spinner!
From the use of simple and low-cost equipment, it is possible to build a good Hand spinner. The video below shows the step by step to build the toy, basically using PVC pipe , Skate bearings and glue.
What does Hand spinner physics consist of ?
There are at least three principles of Physics involved in the operation of the Hand spinner.
A good hand spinner can easily go over a minute of uninterrupted rotation. This is only possible due to the low friction between its components. As the friction between the device components is low, the energy dissipated in the form of heat is very small, so the device can keep rotating for a long period of time.
In some of these devices there are LEDs that, if lit, generate beautiful visual effects. When watching videos of the rotation of a Hand spinner, or even seeing it rotating under a flashing light, one has the sensation that the light points are rotating in the opposite direction to the equipment. This optical illusion is called the strobe effect.
If our eyes or video cameras perceive the luminous points before they complete a spin, the sensation arises that these luminous points execute a movement opposite to the movement of the Hand spinner.
When turning the Hand spinner quickly and tilting it, there is an apparent sensation of the emergence of a force that tries to prevent the device from tilting. This sensation is due to the gyroscopic effect in which a rotating object always tends to keep its axis of rotation pointed in the same direction. The greater the rotation speed of the object, the greater the rotation stability of the system and this will make it difficult to tilt. The physical quantity involved in the gyroscopic effect is angular momentum and its conservation.
In turns, otospeed riders face the gyroscopic effect
This effect is what proves the greater ease of keeping on a bicycle in motion than on a stationary one. When turning corners, motorcycle riders face difficulties imposed by this effect, and one of the solutions found by motorcycle manufacturers is the inversion between the rotation directions of the wheel and the transmission shaft and, thus, the gyroscopic effect is mitigated. .