6. A uniform rigid bar of length l and mass m is supported on two springs and is subjected to a harmonic force F(t) = Fo sin wt, as shown below. The moment of force corresponding to rotational angle is - F(t)l. 51 6 2 F(t) = Fo sin cot Rigid bar Go Copyright 2011 Panon pinga Pence Hall $2k Given = 2 m, m = 1 kg, k = 50 N/m, Fo = 5 N with w = 5 rad/sec, a) write out kinetic and potential energies of the bar in terms of its mass center displacement x and its rotational angle 0, b) using Lagrange's equation, derive the equation of motion of the bar, c) find the steady-state response caused by F(t) using the mechanical impedance method.