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.
Springfield is the third largest city in the state of Missouri and the county seat of Greene County. According to the 2010 census data, the population was 159,498, an increase of 5.2% since the 2000 census. It is one of the two principal cities of the Springfield-Branson Metropolitan Area, which has a population of 537,631 and includes the counties of Christian, Dallas, Greene, Polk, Webster, Stone and Taney.