In this experiment we measure Earth’s gravitational acceleration g by timing the swing of a simple pendulum — and, more importantly, we compute our own measurement uncertainty. The simulation below includes hidden systematic errors (ruler and stopwatch) and random errors (your reaction time), so when you compare your result with the true value you can identify the sources of error.
Before you start, watch this video
Above the simulation, the legendary lecture by MIT’s Professor Walter Lewin is embedded — he hangs himself from a 5-meter pendulum to show the period is independent of mass. That is exactly what the formula T = 2π√(L/g) predicts — no m anywhere.
A second way to measure the same g
You can measure the same quantity by a totally different technique: the free-fall experiment. Compare the two results — the classic exercise of the scientific method: one quantity, two independent methods, cross-check.