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Materials

Water Bridge

Start with the video, then use the science notes and recommended parts below to follow the idea behind the build.

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How it works

What this project is testing.

A water bridge looks impossible at first: distilled water climbs out of one beaker and holds a thin liquid bridge to another when high DC voltage is applied.

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The demo shows a tug-of-war between electric forces, surface tension, flow, heating, and gravity. Distilled water matters because ions make the setup leak current and heat up instead of forming a clean bridge.

E \approx \frac{V}{d}

The field strength rises with voltage and falls as the beaker gap grows.

u = \frac{1}{2} ϵ E^{2}

Electric field energy density gives a useful scale for the stress helping support the bridge.

Recommended parts

Products used in this project.

Affiliate links may earn Keystone Science a commission. Match ratings, values, sizes, polarity, and safety requirements to your own build before buying.

DEVMO DC 3V-6V to 400kV 400000V Boost Step-up Power Module High-Voltage Generator

high-voltage power supplypower

DEVMO DC 3V-6V to 400kV Boost Step-up High-Voltage Generator Module

$10.994.4(508)

Prefer low-current educational modules over mains-powered high-voltage supplies. Review requirements and safety guidance before buying.

MECCANIXITY Graphite Block Ingot Rectangle Graphite Electrode Plate Board 100x20x5mm for Melting Casting, Electrolysis Electroplating, Pack of 5

electrodeschemistry/electrical

MECCANIXITY Graphite Electrode Plate Board, 100x20x5mm, Pack of 5

$9.394.6(53)

Good functional match, but sparse Amazon review evidence. Review requirements and safety guidance before buying.

Pure Life Distilled Water 2.5 Gallon, 320 Fl Oz

waterfluid

Pure Life Distilled Water, 2.5 Gallon

$5.694.6(410)

2 x 13.5 Pounds Arm & Hammer Pure Baking Soda (27 Pounds Total)

salt / electrolytechemistry

Arm & Hammer Pure Baking Soda, 2 x 13.5 Pounds

4.8(1,100)

For electrolysis demos, baking soda is often a safer electrolyte than table salt.

Ackers High Borosilicate Glass Measuring Cup Set with Pour Spout,60ml(2OZ),120ml(4OZ), 250ml(8OZ) Glass Measuring Beaker for Kitchen or Restaurant, Easy to Read

glassfabrication

Ackers High Borosilicate Glass Measuring Beaker Set with Pour Spout

4.5(3,500)

EDGELEC 120pcs Breadboard Jumper Wires 20cm Wire Length Optional Dupont Cable Assorted Kit Male to Female Multicolored Ribbon Cables

jumper wires / hookup wirewiring

120pcs Breadboard Jumper Wires, 20cm Dupont Cable Assorted Kit, Male to Female

$6.984.7(4,500)

Project files

Prints, kits, and downloads.

Diagrams, printable files, kits, or companion downloads will appear here when they are ready to use.

Coming soon

Contact

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