This small group activity is designed to help upper-division undergraduate students understand the quantitative relationship between the period and amplitude for a plane pendulum.

Students derive the expression for the period of a plane pendulum from the equations of motion, evaluate the integral expression numerically using series expansion or a computer program (Maple/Mathematica), and plot the experimental and numerical results on the same graph.

The wrap-up discussion focuses on techniques for simplifying the integral expression of the period and on the quantitative agreement of the model and experiment.