1) Considering both elastic and inelastic collisions, does the momentum after a collision always equal the momentum before the collision?
2) Considering both elastic and inelastic collisions, does the kinetic energy after a collision always equal the kinetic energy before the collision?
3) Consider a theoretical head-on collision between two carts of equal mass and equal speed.
a. What is the total momentum before the collision?
b. What is the total momentum after the collision?