To find the momentum of a pendulum at its lowest point, one must understand the concepts of momentum, kinetic energy, and gravitational potential energy. The pendulum swings from a height determined by its starting angle θ, converting potential energy into kinetic energy as it descends. At the lowest point, all potential energy is transformed into kinetic energy, allowing for the calculation of momentum using the formula p = mv, where v is the velocity at that point. The discussion emphasizes the importance of grasping these fundamental concepts to solve the problem effectively. Understanding these principles is crucial for accurately determining the pendulum's momentum.