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.
According to our research of Illinois and other state lists there were 307 registered sex offenders living in Springfield, Illinois as of April 15, 2017. The ratio of number of residents in Springfield to the number of sex offenders is 382 to 1. Nearest city with pop. 200,000+: St. Louis, MO (86.0 miles , pop. 348,189).