Answer: 2 seconds.
- A 2 seconds
- B 1 second
- C 4 seconds
- D 0.5 seconds
Correct answer: A. 2 seconds
Explanation: A seconds pendulum has T = 2 s (it takes 1 second for each half-swing, completing a full cycle in 2 seconds). Its length at Earth surface is about 1 m.
In SHM, displacement and velocity are 90° out of phase (v is maximum when x=0, and zero when x is extreme), while acceleration is always exactly opposite in sign to displacement, consistent with a = −ω²x.
Concept context
Simple harmonic motion, spring-mass, pendulum, energy in SHM, and resonance.