Perfect Educational Newton BallAccording to the law of conservation of momentum and energy, the metal ball will not swing forever because of resistance. Usually, under normal conditions, the ball will swing for about 15-30 seconds. However, due to different forces and circumstances, the swing time will also vary. Excellent table top decorationThis is a very interesting decompression Newton ball, one ball can hit other balls and swing. (mini rocking basketball, please don't shake the metal ball hard) It is very suitable for the decoration of indoor places such as office and home. Stress ReliefNewton Balance Ball is suitable for children and adults, it is perfect for eliminating boring time and relieve stress. Pull one or more balls, release them and the same number of balls will swing on the other side. Best Choice for GiftsThe cradle with cradle can explain children's physics knowledge and Newton's story, and can also help you explore the mysteries of natural science. This is a fun gift for your friends, family and kids. Buy with confidenceFrom purchasing raw materials to factory inspection of products, we will carry out inspections in each link, and each link has a record. The registrations for each quality control link in the production process are very strict, so you can buy with confidence.