Answer: 4 m/s2.
- A 1 m/s2
- B 4 m/s2
- C 2 m/s2
- D 5 m/s2
Correct answer: B. 4 m/s2
Explanation: Driving force = P/v = 50000/10 = 5000 N. Net force = 5000 - 1000 = 4000 N. a = 4000/1000 = 4 m/s2.
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.