Answer: 6.28 s.
- A 3.14 s
- B 1.57 s
- C 12.56 s
- D 6.28 s
Correct answer: D. 6.28 s
Explanation: v = ω√(A<sup>2</sup> - x<sup>2</sup>) gives 8 = ω√(100 - 36) = 8ω, so ω = 1 rad/s. Then T = 2π/ω = 6.28 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.