What does it mean to say that momentum is conserved? when momentum or any other object in physics doesn't change..... momentum = momentum before and after the collision. Elastic collision
The 2016 Springfield, Illinois, population is 116,565. There are 1,955 people per square mile (population density). The median age is 38.7. The US median is 37.4. 44.11% of people in Springfield, Illinois, are married. 14.83% are divorced.
The Springfield Metropolitan Statistical Area, as defined by the United States Census Bureau, is an area consisting of two counties in Central Illinois, anchored by the city of Springfield. As of the 2000 census, the MSA had a population of 201,437 (though a July 1, 2009 estimate placed the population at 208,182). Springfield is south of Peoria, Illinois, Pekin, Illinois, and Lincoln, Illinois; southwest of Bloomington, Illinois and Champaign, Illinois; and west of Decatur, Illinois. The southern portion of the Springfield metropolitan area is north of the Metro-East, the Southern Illinois portion of the Greater St. Louis area.