Answer: 0.897 s.
- A 0.897 s
- B 0.45 s
- C 2.83 s
- D 0.2 s
Correct answer: A. 0.897 s
Explanation: At equilibrium: kx = mg → k = mg/x = 2×10/0.2 = 100 N/m. T = 2π√(m/k) = 2π√(2/100) = 2π × 0.1414 ≈ 0.889 s.
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.