Answer: 6 m/s.
- A 6 m/s
- B 12 m/s
- C 20 m/s
- D 60 m/s
Correct answer: A. 6 m/s
Explanation: Useful power = 0.3 x 10000 = 3000 W. Max speed = P/F = 3000/500 = 6 m/s.
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.