Happy and Sad Balls are used to show the relationship between elastic and inelastic collisions. While both balls share an identical makeup between mass, density, and appearance, one will bounce, while the other will not. They are sold as a pair.
The Happy Ball consists of standard neoprene that has low hysteresis, low surface friction, and weak intermolecular forces. The Sad Ball consists of Norsorex that has high hysteresis, high surface friction, and stronger intermolecular forces.
Instructions included.
PRODUCT WARNINGS
WARNING: This product can expose you to chemicals including benzene and lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
This product contains latex, which can cause allergic reactions in some people. If symptoms of an allergic reaction occur, stop use immediately and consult a physician.
This product consists of small balls, making it a choking hazard. Only use with adult supervision.
Our products are not toys. Use in a laboratory or educational setting only. Not for children 13 and under.