Practice question

**Oscillation of mass attached to spring** follows Hooke's law F = -k x, SHM with ω = √(k/m). Effective stiffness for two identical springs in parallel doubles, k_eff = 2k, increasing frequency by √2, while series halves stiffness to k/2, lowering frequency. Energy E = ½ k_eff A². Effective kₑff = 2k = 2 × 75 = 150 N/m . ω = √((kₑff/m)) = √((150/1.5)) = √(100) = 10 rad/s . v = (ω/2π) = (10/2 × 3.14) ≈ 1.59 Hz . Applying x = A cos(ωt + φ), v = -ωA sin(ωt + φ), a = -ω²x and E = ½kA² = ½mω²A², result