Practice question

**Conservation of mechanical energy** in undamped SHM implies total energy proportional to amplitude squared A² and spring constant k. E = ½ k A² allows amplitude determination from known E and k via A = √(2E/k), with k = m ω² linking dynamical and energetic descriptions for spring-mass system. Total energy: E = (1/2) k A² = 0.5 × 100 × (0.15)² = 1.125 J . Potential energy: U = (1/2) k x² = 0.5 × 100 × (0.075)² = 0.28125 J . Kinetic energy: K = E - U = 1.125 - 0.28125 = 0.84375 J . Applying x = A cos(ωt + φ),