Experimental investigation of the stability of the floating water bridge

TL;DR

This study experimentally investigates the stability of the floating water bridge formed under high voltage, confirming that dielectric and surface tension forces maintain its stability despite microscopic water structure changes.

Contribution

It provides experimental validation that macroscopic dielectric and surface tension forces explain the stability of the floating water bridge.

Findings

Dielectric tension and surface tension are key to bridge stability.

Experimental results align with theoretical predictions.

Stability is governed by macroscopic forces, not microscopic water structure.

Abstract

When a high voltage is applied between two beakers filled with deionized water, a bridge of water may be formed in between exceeding the length of 2 cm when the beakers are pulled apart. We construct experiments in which the geometry and the electric field within the bridge are measured and compared with predictions of theories on the floating water bridge. A numerical simulation is used for the measurement of the electric field. Our experimental results approve that two forces of dielectric tension and surface tension are holding the bridge against gravity. These forces have the same order of magnitude. Results show that the stability can be explained by macroscopic forces, regardless of the microscopic changes in water structure.