Some information of Collisions in these notes.

1. Momentum is conserved

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

2. There is no sound in the collision (or very little sound).

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

3. Kinetic energy is conserved.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

4. Kinetic energy is not conserved.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

5. The objects are damaged, dented, deformed, or destroyed.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

6. The objects stick together or are combined afterward.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

7. A football player catches a football.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

8. A football player is hit by the football, but does not catch it.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

9. The objects collide and do not combine.

   1.   ?    Elastic
   2.   ?    Inelastic
   3.   ?    Perfectly Inelastic
   4.   ?    Inelastic and Perfectly Inelastic
   5.   ?    Elastic and Inelastic
   6.   ?    All Collisions

10. A person jumps into a boat.

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

11. Two objects slam into each other, remain independent afterward, and kinetic energy is not conserved.

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

12. Two objects slam into each other, remain independent afterward, and kinetic energy is conserved.

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

13. A loud collision.

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

14. Σp_before = Σp_after, ΣE_kbefore does not = ΣE_kafter

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

15. Σp_before = Σp_after, ΣE_kbefore = ΣE_kafter

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions

16. Σp_before = Σp_after, ΣE_kbefore does not = ΣE_kafter, m_after = m₁ + m₂.

    1.   ?    Elastic
    2.   ?    Inelastic
    3.   ?    Perfectly Inelastic
    4.   ?    Inelastic and Perfectly Inelastic
    5.   ?    Elastic and Inelastic
    6.   ?    All Collisions