As the pendulum moves from point 2 to point 3, what happens to its mechanical energy? potential energy is converted to kinetic energy and back again. kinetic energy is converted to potential energy only once. potential energy is converted to kinetic energy only once. kinetic energy is converted to potential energy and back again.

Potential energy is converted to kinetic energy and back again.

Explanation:At points 1 and 3, the pendulum stops moving, and its mechanical energy is purely potential. At point 2, the pendulum is moving the fastest, and its mechanical energy is purely kinetic. Therefore, as the pendulum moves from point 1 to point 3, its potential energy is first converted to kinetic energy, then back to potential.

plasma - state of matter made up of electrically charged particles