Problem 1: A uniform rod of mass M and length L is free to swing back and forth by pivoting a distance x = L/4 from its center. It undergoes harmonic oscillations by swinging back and forth under the influence of gravity. In terms of M and L, what is the rod's moment of inertia I about the pivot point. Calculate the rod's period T in seconds for small oscillations about its pivot point. M= 1.2 kg and L = 1.1 m Ans: The rod is not a simple pendulum, but is a physical pendulum. The moment of inertia through its center is 1 = ML? + M(L/4)2 = ML? +1 Ml2 =0.146 ML? For small oscillations, the torque is equal to T = -mgsin(0) XL/4 = la For small amplitude oscillations, sin(0) - 0, and a = -w20 12 12 16 Therefore w = mg(L/4) 1.79 -(1) Finally, the period T is related to o as, w=270/T.............(2) Now you can plug the value of g and L and calculate the time period.