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 Metro and two are in operation. Dalian Metro The Dalian Metro or Dalian Subway is a rapid transit system in the city of Dalian, Liaoning, China. The metro opened on 1 May 2003. The system currently in operation consists of 4 lines: Line 1, Line 2, Line 3, and Line 12. Line 1, opened in 2015 currently in operation, connects east southeast central Dalian with north Dalian. The total length is 28.34 kilometers, with 22 underground stations. Line 2, opened in 2015 currently in operation, connects east central Dalian with west central Dalian. The total length is 42.56 kilometers, with 29