1. The problem statement, all variables and given/known data A horizontal plank (mass 2kg, length 1m) is pivoted at one end. A spring (k=1000N/m) is attached at the other end. Find the angular frequency for small oscillations. Answer: ω=39rad/s 2. Relevant equations ω = √(mgd + kΔxd/I) I think I would be treating the plank as a long thin rod with rotational axis through the end (since I'm not provided with the dimensions of the plank), so I = 1/3mL2 + md2 Where L: length of the rod, d: distance between pivot and rod's centre of mass (d=L/2) 3. The attempt at a solution I = 1/3mL2 + md2 = 1/3mL2 + m(L/2)2 ω = √(mgd + kΔxd/I) mgd component --> mg(L/2) kΔxd component --> mg(L/2)2 Substituting all the known values... ω = √[(2)(9.8)(1/2) + 1000(12)] / [(1/3)(2)(12) + 2(1/2)2] ω = √1009.8/1.16 = 29.4 Still not getting the correct answer.