Features: 
Principle: Not only demonstrates a pendulum, but also shows the Laws of Conservation of Momentum and Energy. 
Material: Balance Balls Desk Toy * 1, Stainless steel frame and balls, Nylon thread.
Attention: Friction and damping effects are inevitable.
Pioneering developments for several years, welldone have been focusing on the exquisite technologies and physics tools. This classic desktop toy provides you many benefits and entertainments, is suitable for various locations such as house or office, and is an intriguing device that not only demonstrates pendulum motion, but also helps to show the laws of Conservation of Momentum and Energy. Whether you are studying physics knowledge, working on complex analysis, or looking for a delicate gift, this Garget is definitely what you really want. 
A Brief History
Newton's cradle, named after Sir Isaac Newton, is a device that demonstrates three main physics principles: conservation of energy, conservation of momentum and friction via a series of swinging spheres. 
Most people think that Isaac Newton invented the apparatus commonly called a Newton's Cradle, but he didn't. English actor Simon Preble invented the device in 1967 and named it in honor of Newton. In 1968 the first portable version hit the market and quickly gained popularity around the world as a fun, educational physics demonstrator. 

• MATERIAL---Durable WOOD base, nylon strings, metal balls, stainless steel frame
• SWING TIME---The balls continue in perpetual motion FOR ONLY 15-25 SECONDS due to the resistance of the air and friction
• ISADVANTAGE---We can not create a vacuum environment, so the balls will have some space when it is working, but it won't influence the effect of playing
• APPLICABILITY ---You can put it on your office desk or your home desk or on your shelf. It will be cool desk toy
• AFTER-SALE WARRANTY -- If, for any reason, you are not completely satisfied, please contact us by email so that we may address your concerns

MATERIAL---Durable WOOD base, nylon strings, metal balls, stainless steel framewelldone