Perfectly elastic collisions are those in which no kinetic energy is lost in the collision. Macroscopic collisions are generally inelastic and do not conserve kinetic energy, though of course the total energy is conserved as required by the general principle of conservation of energy.
Ector, Texas. Not to be confused with Ector County, Texas. Ector is a city in Fannin County, Texas, United States. The population was 695 at the 2010 census, up from 600 at the 2000 census.
Medina County, Texas. Medina County is a county located in the U.S. state of Texas. As of the 2010 census, its population was 46,006. Its county seat is Hondo. The county is named for the Medina River. The Medina Dam, the fourth largest in the nation when completed in 1913, is listed on the National Register of Historic Places.