Answer: x=0 (equilibrium).
- A x=0 (equilibrium)
- B x=A (amplitude)
- C x=A/2
- D x=A*sqrt(2)
Correct answer: A. x=0 (equilibrium)
Explanation: Total energy = KE + PE. At x=0, PE = 0, so all energy is KE. Total energy = KE only at equilibrium.
As a pendulum swings, total mechanical energy (KE+PE) stays constant: at the highest points A and C, all energy is potential (zero speed); at the lowest point B, all of that energy has converted into kinetic energy (maximum speed).
Concept context
Work-energy theorem, potential energy, conservation of energy, collisions.