... the mass of the pendulum arm provides torque and must be described using Newton's second law for rotation: ? = Iarm?, and the torque is ? = -mgLcmsin ?. This leads to the equation for the period of a compound pendulum: T = 2??(Iarm/mgLcm) which is similar in form to the simple pendulum equation, adding the compensation for the moment of inertia inherent in the arm of the pendulum. A pendulum is suitable for experiments in simple harmonic motion, because it provides a motion similar to a vertical spring oscillating up and down (or back and forth for a horizontal spring). This is because gravity provides the force to move the pendulum initially from its point of all potential energy to its point of all kinetic energy. In the absence of friction and air resistance, a pendulum would oscillate forever in simple harmonic motion, much the way an ideal spring would. In this experiment, ...

See this essay or coursework document in full right now