1. The problem statement, all variables and given/known data A 10lb bar is pinned at its center O and connected to a torsional spring. The spring has a stiffness k = 5 lb ft/rad so that the torque develped is M = 5(theta) lb ft where theta is in radians. If the bar is released from rest when it is vertical at theta = 90 degrees, determine its angular velocity at the instand theta = 45 degrees 2. Relevant equations I(o) = .5mr^2 Moment = I(o)a where a is angular acceleration w^2 = w(o)^2 + 2a(theta - theta(initial)) 3. The attempt at a solution 10lb = .3108 slug I = .5(.3108)(1^2) = 1.554 sluf ft^2 Moment = Ia 5theta = 1.554a a = 32.1750theta 90 degrees = 1.5708 radians 45 degrees = .7854 radians w^2 = 0 + 2(32.1750)(.7854)(.7854 - 1.5708) w = 6.3004 rad/s Should the inital theta be 0.