Product Overview

The Coulomb’s Law Apparatus provides a stable, high-precision setup for investigating the electrostatic force between charged spheres. Students can verify the inverse-square relationship, measure Coulomb force at different separations, and determine how charge magnitude and environmental factors influence results. Its symmetrical design, clear measurement scales, and built-in damping allow for accurate, repeatable data collection in teaching laboratories.

Key Features

Precision torsion balance with an angular scale for accurate measurement of wire twist
Magnetic damping system that stabilizes movement and speeds up measurement time
Calibration masses included for determining the torsion constant and verifying linear response
Insulated linear track engineered to reduce stray and mirror-charge effects
Integrated millimeter scale for precise control of sphere separation
Charge adjustment sphere for reliably reducing or dividing charge in known ratios
Symmetrical construction to minimize field distortion and improve measurement accuracy

How It Works

A conductive sphere is mounted on a counterbalanced insulating arm suspended from a thin torsion wire. A second identical sphere is positioned on an adjustable insulated track. When the spheres are charged, the electrostatic force causes the suspended arm to rotate. Re-balancing the torsion arm and reading the twist angle allows students to calculate the force. This straightforward setup supports both introductory verification of Coulomb’s law and more advanced studies involving material, environmental, and charge-distribution variables.

Possible Investigations

Force–distance measurements to verify the inverse-square law
Determination of Coulomb’s constant
Study of the effect of varying charge magnitude
Influence of dielectric materials on force measurements
Environmental effects such as humidity and temperature on electrostatic behavior