Science Magic Series / Obedient Bamboo Dragonfly-Nianli Stick

https://5993.cyberbiz.tw/s/files/5993/ckeditor/pictures/content_5898e00e-5195-46d0-aa60-25a422c2e970.jpg Gee-haw whammy diddle It is a scientific toy that converts vibration into rotation. The principle is similar to that of a hula hoop. The speed of the fingers can be used to cause different vibration frequencies of the stick body. When the frequency and the blade speed match and are in phase, the propeller blades are accelerated to rotate. <Small tips! > If you want to accelerate the propeller blades from a standstill, you must first scrape the serrated portion at a low speed and gradually increase the scraping speed. https://5993.cyberbiz.tw/s/files/5993/ckeditor/pictures/content_4e3d36fa-027f-4e35-b200-32844f717f18.jpg https://5993.cyberbiz.tw/s/files/5993/ckeditor/pictures/content_53f48e30-cdcf-48ba-b0ab-f256bb3db010.jpg <Science Tips> This science toy uses two scientific principles (1) Elliptical vibration direction The direction of the elliptical motion of the stick vibration causes the direction of friction at the initial and other times, so that the positive reversal of the propeller can be caused by the upper right and upper left edges of the friction serration. (2) Synchronous acceleration mode Like the principle of a hula hoop, the propeller and the bearing shaft are eccentric. For the center of gravity of the propeller that is performing a circular motion with respect to the bearing shaft, if the bearing shaft makes a motion perpendicular to the tangential speed of the center of gravity, it will cause The center of gravity adds a component of vertical velocity change to increase the velocity, which in turn accelerates the rotation. This phenomenon must be synchronized and continuously occurred during the vibration process to continue to accelerate. If it is not synchronized, the overall effect is low and the propeller is decelerated due to friction loss. . (transferred from: wikipedia) Product specifications: ► Size: 13 x 6 cm (after assembly) ► Material: Plastic ► Manufacturing location: China Precautions: ► 1. Please stay away from fire ► 2. Contains small parts, please avoid eating