Mechanical energy mechanical energy of the colliding objects has been converted into an equal amount of heat. Thus, the total energy of the system remains unchanged though the mechanical energy of the system has reduced. A satellite of mass formula_4 at a distance formula_5 from the centre of Earth possesses both kinetic energy, formula_6, (by virtue of its motion) and gravitational potential energy, formula_7, (by virtue of its position within the Earth’s gravitational field; Earth's mass is formula_8). Hence, mechanical energy formula_9 of a satellite is given by If the satellite is in circular orbit, the energy conservation equation can be further
Dandong–Dalian intercity railway and a half years and was started on 17 March 2010. It started operation on 17 December 2015. Dandong–Dalian intercity railway The Dandong–Dalian intercity railway () is a high-speed line operated by China Railway High-speed within the Liaodong Peninsula of Liaoning province, connecting the coastal cities of Dandong and Dalian. Dandong–Dalian intercity railway is broken down into three segments: Dandong–Zhuanghe, Zhuanghe–Dengshahe, and Dengshahe–Dalian. It will have a total length of about , of which will be in the Dandong prefectural area, will be in the Dalian region. The total investment is estimated to be about 14.7 billion yuan with a