Introducing Newton, affectionately named after 17th century English mathematician and physicist, Isaac Newton. (1642-1724) Newton’s third law of motion applies to collisions between two objects. In a collision, both objects experience forces equal in magnitude and opposite in direction. This pooch features a railroad track adze for a head and an auto body finishing hammer for a tail, and five 4 lb. hand sledges make up what is known as a “Newton’s Cradle”. Even though his mathematical equation is kg-m/s squared, he prefers to be called Newton.