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High-voltage build

Jacob's Ladder

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

High voltageBuild

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How it works

What this project is testing.

A Jacob ladder is the classic rising-arc demo: high voltage jumps across a small gap, turns air into plasma, and creates a bright conductive path.

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The arc climbs because the hot ionized air rises. As the rods spread farther apart, the gap eventually becomes too large for the voltage to sustain, so the arc snaps out and restarts near the bottom.

E \approx \frac{V}{d}

The electric field gets stronger when the same voltage is forced across a smaller gap.

P = I V

Electrical power in the arc becomes heat, light, sound, and moving air.

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.

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)

BOJACK 20 Values 200 Pcs Inductor 10 uH to 10 mH 1 W Color Ring Inductor 1 Watt Assortment Kit

inductor / coilpassive electronics

20 Values 200 Pcs Inductor Assortment Kit, 1uH to 4.7mH, 0.5W Color Ring Inductors

$13.994.8(182)

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Jack Converter, 12 Volt LED Driver 24W Adapter Transformer for Strip Lights, Surveillance Cameras, External HDD, Monitor, CCTV (Pack of 1)

transformerpower

12V 2A Power Supply, AC 120V to DC12V 5.5x2.1mm Adapter Transformer

$8.994.5(6,601)

General low-voltage transformer/adapter pick; match voltage/current and connector to the circuit.

ZVS Driver Module 12V to 30V DC High Voltage Generator with Flyback Transformer Heater Coil Boost Power Supply Board for Induction Heating

flyback transformerhigh voltage

ZVS Driver Module with Flyback Transformer, 12V-30V DC High Voltage Generator

$37.504.4(55)

High-voltage specialty part. Review ratings and safety language before public recommendation. Review requirements and safety guidance before buying.

CQRobot Speaker 3 Watt 8 Ohm Compatible with Arduino Motherboard, JST-PH2.0 Interface. It is Ideal for a Variety of Small Electronic Projects.

speakeraudio

CQRobot 3 Watt 8 Ohm Speaker for Arduino and Small Electronics Projects

$7.994.5(457)

Etauwe 5/16" Diameter 8" Length 304 Stainless Steel Solid Round Rod, Metal Solid Shaft Rods, for DIY Craft and Metal Working,

Jacob's ladder electrodeshigh voltage

304 Stainless Steel Solid Round Rods, 1/8 inch Diameter, 16 inch Length, 10pcs

$9.994.6(196)

Electrode material only; do not imply this is a full Jacob's ladder kit.

Plywood Board 20PCS 12" x8" x 1/12 inch Basswood Sheets Thin Wood Sheets Perfect for Arts Crafts School Projects and DIY Projects,Baltic Birch Sheets Perfect for Wood Burning…

woodfabrication

Plywood Board 20PCS 12 x 8 x 1/12 inch Basswood Sheets for Arts, Crafts, School Projects, and DIY

$19.994.6(2,300)

TOSHIBA EM131A5C-BS Countertop Microwave Ovens 1.2 Cu Ft, 12.4" Removable Turntable Smart Humidity Sensor 12 Auto Menus Mute Function ECO Mode Easy Clean Interior Black Color 1000W

microwave ovensalvage

Toshiba EM131A5C-BS Countertop Microwave Oven, 1.2 Cu Ft, 1000W

$148.994.4(32K)

Recommend only as an appliance; do not encourage buying a working microwave for disassembly. Review requirements and safety guidance before buying.

NoCry Clear Safety Glasses for Men and Women with Anti-Fog and Scratch Resistant Wrap Around Lenses, Adjustable Temples and Nose Pads — ANSI Z87 Certified Protective Eyewear with 100% UV Shielding

safety glassessafety

NoCry Clear Safety Glasses with Anti-Fog and Scratch-Resistant Wraparound Lenses, ANSI Z87 Certified

$13.984.5(49K)

Sand Paper, 48 PCS Sandpaper, 120 to 5000 Assorted Grit Sandpaper Sheets, 9 x 3.6 Inch Premium Wet Dry Sandpaper for Wood Fur

sandpaperfabrication

Fandeli Assorted Grit Sandpaper Sheets

$12.99

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

Events, speaking, collaborations, and news.

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