A large pendulum with a 200 lb gold-plated bob 12 inches in diameter is on display in the lobby of the United Nations building. It is used to show the rotation of the Earth -- for this reason it is referred to as a Foucault pendulum. If the pendulum is 19.7 m in length, what is the least amount of time it takes for the bob to swing from a position of maximum displacement to the equilibrium position of the pendulum? (Assume that the acceleration due to gravity is g = 9.81 m/s2 at the UN building.)