This apparatus is designed to study the simple harmonic motion of a torsional pendulum. It consists of a plate with central hole equipped with two pulleys with ball bearing. A rod with a central cylindrical mass act as the pendulum. With this apparatus one can study the torsional pendulum constant dynamically as well as in the static case. The torsional pendulum is an angular version of a simple harmonic oscillator. Instead of back and forth motion like in the case of a spring the restoring force is actually a restoring torque causing the pendulum to rotate backwards to equilibrium.This kit explores the two distinct ways to determine the torsional spring constant of the wire; one that involves a dynamic system like a regular pendulum swinging back and forth and the other a static system akin to one way of measuring the restoring force of a spring.Kit Includes:Heavy Duty BaseSquare Support RodPlate with Central HoleHanger Bracket with Graduated DrumBrass Torsion Pendulum2 x Brass Outer Discs8 x 10g Masses2 x Weight Hangers7 x Torsion Lines (various diameters & lengths)Instructional Guide