A reversible pendulum that made possible an extremely accurate measurement of the acceleration due to Earth's gravity, g. The reversible pendulum is a pendulum that can be swung from either of two pivot points. When the mass distribution of the pendulum is adjusted so that the periods are the same from either pivot, then the period is the same as a simple pendulum having a length equal to the distance between the pivots. While this may seem to be a simple property, it has great power in determining the value of g to high accuracy. During a typical three-hour laboratory session, a student should be able to measure g to an accuracy of ±0.1%. The Kater's Pendulum is crafted from nickel-plated steel with polished brass bobs.
