Mechanical energy swing because of the work done by the pendulum to oppose these non-conservative forces. That the loss of mechanical energy in a system always resulted in an increase of the system's temperature has been known for a long time, but it was the amateur physicist James Prescott Joule who first experimentally demonstrated how a certain amount of work done against friction resulted in a definite quantity of heat which should be conceived as the random motions of the particles that comprise matter. This equivalence between mechanical energy and heat is especially important when considering colliding objects. In an elastic collision,
Dalian Minzu University . Dalian Minzu University has a good reputation in both engineering and science programs. The university also offers programs in business, economics, arts, and management. It has 40 bachelor's degree programs and 14 colleges, including: The campus is large and has comprehensive modern teaching and research equipment. Fifteen state and provincial key laboratories have been established one after another throughout the years. Dalian Minzu University Dalian Minzu University () is located in Dalian, Liaoning, People's Republic of China and directly supervised by the State Ethnic Affairs Commission. Dalian Minzu University was founded in 1997. As the only Nationalities University focusing