Simple Pendulum - Physics Demonstrations - Simple Pendulum | Physics Undergraduate Labs

Always verify the crank handle is properly secured in one of the depressions before releasing the bob. An unsecured handle allows the string to extend freely, converting the pendulum into an unintended freefall demonstration.

Purpose

A simple pendulum with easily adjustable string length demonstrates how period depends on length: $T = 2\pi\sqrt{L/g}$ . The bright yellow bob is visible even in the largest lecture halls.

Yellow chalk-line bob swinging on a short string from a horizontal rod on a clamp stand, with motion blur showing a wide arc in front of a chalkboard

Yellow chalk-line bob swinging on a longer string from the same clamp stand, with motion blur showing a narrower arc

Figure 1: The pendulum at maximum amplitude shows the curved yellow housing that makes the bob visible in large classrooms. The suspension system allows easy adjustment of string length during demonstration.

Figure 2: Motion blur captured with identical exposure time demonstrates faster swing speed at shorter string length, visually confirming the period-length relationship $T \propto \sqrt{L}$.

Chalk Line Plumb Bob

1

Safety Warnings

Warning: Handle Mechanism Critical

Purpose