3. The simple pendulum system in the figure undergoes free oscillation motion. a. Assuming that the angle 0 < 20, derive the equation of motion of the system using the energy method. (Neglect the mass of the rod). b. Calculate the natural frequency of the system if m = 0.783 kg and L = 0.5 m. L Acceleration of Gravity Lagrange equation for conservative systems Total energy equation for conservative systems 9.806 m/s d T -+- -- dt aqu ` dE E=T+V | = 0 dt m