Answer: Both KE and momentum.
- A Kinetic energy mainly
- B Momentum mainly
- C Both KE and momentum
- D Neither in typical laboratory settings
Correct answer: C. Both KE and momentum
Explanation: In an elastic collision, both kinetic energy and momentum are conserved.
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.