Linear Momentum and Collisions

Part 6: Linear Momentum and Collisions

This part introduces linear momentum, another fundamental conserved quantity in physics. While energy is useful for analyzing many physical systems, momentum provides a powerful framework for understanding collisions, explosions, and interactions between objects. You will learn how force changes momentum, how impulse describes the effect of forces acting over time, and why the conservation of momentum applies whenever external forces are negligible.

The concepts developed in this part have many applications in medicine, biology, and engineering. Momentum and impulse are essential for understanding sports injuries, automobile safety systems, falls, prosthetic design, and the biomechanics of walking and running. They also explain how airbags, helmets, and protective equipment reduce injury by increasing the time over which a collision occurs. Finally, you will extend these ideas to collisions in two dimensions and discover how the same conservation laws explain the motion of rockets and spacecraft.

This part contains the following chapters:

51. Introduction to Linear Momentum and Collisions
52. Linear Momentum and Force
53. Impulse
54. Conservation of Momentum
55. Elastic Collisions in One Dimension
56. Inelastic Collisions in One Dimension
57. Collisions of Point Masses in Two Dimensions
58. Introduction to Rocket Propulsion