Master the Mechanics: NCEA Level 3 Physics 2025 – Get Ready to Rock Your Exam!

The primary role of potential energy in a pendulum's movement is to convert into kinetic energy at the lowest point of the swing. As the pendulum moves away from its lowest position, it gains height, and its potential energy increases while its kinetic energy decreases. At the highest points of the swing, the potential energy is maximum because the height is greatest, and the kinetic energy is minimal due to the slower speed of the pendulum.

As the pendulum swings back down towards the lowest point, the potential energy is converted into kinetic energy. At the lowest point, the speed of the pendulum is at its maximum, and thus kinetic energy reaches its peak while potential energy is at a minimum. This interplay between potential and kinetic energy is what allows the pendulum to continue its swinging motion, demonstrating the conservation of mechanical energy as the total energy (potential energy + kinetic energy) remains constant in an ideal system without friction or air resistance.