This physics video tutorial explains how to solve conservation of momentum in two-dimension physics problems. The total momentum in the x direction and in the y direction must be conserved separately. Inelastic Collisions occur when momentum is conserved when kinetic energy is not conserved especially in the case when two objects stick together after a collision. Elastic collisions occur when both momentum and kinetic energy are conserved. Objects bouncing off each other usually occur during an elastic collision. Momentum - Free Formula Sheet: Physics 1 Final Exam Review: Physics PDF Worksheets: Final Exam and Test Prep Videos: ___________________________ Impulse and Momentum: Conservation of Momentum: Rocket Propulsion: What Really Is a Force? Inelastic Collisions: ______________________________ Impulse Momentum Theorem: Force-Time Graphs: Ballistic Pendulum Problem: Elastic Collisions: Impulse & Momentum Test Review: _____________________________ Center of Mass Problems: Center of Mass - Calculus: Intro to Rotational Motion: Full-Length Videos and Worksheets: