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High-voltage build

High voltage Capacitor

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 capacitor stores energy by separating charge across an insulating layer. High voltage makes that stored field stronger, which is useful for demos but also why capacitors can remain dangerous after power is removed.

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The experiment demonstrates what sets capacitance and voltage limits: plate area, spacing, dielectric material, and the point where the insulator finally breaks down.

C = ε \frac{A}{d}

Capacitance increases with plate area and dielectric strength, and decreases as plate spacing grows.

U = \frac{1}{2} C V^{2}

Stored energy rises with capacitance and with the square of voltage.

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 24Value 630pcs Aluminum Electrolytic Capacitor Assortment Box Kit Range 0.1uF－1000uF

capacitorpassive electronics

BOJACK 24-Value 630pcs Aluminum Electrolytic Capacitor Assortment Box Kit, 0.1uF-1000uF

$16.994.7(953)

SYCZIOHU Universal Microwave Oven High Voltage Capacitor 2100V 1.05 MFD uF Household Microwave Replacement Part

high-voltage capacitorpassive electronics

Universal Microwave Oven High Voltage Capacitor, 1.05 MFD

$11.994.4(345)

High-voltage capacitors retain dangerous charge. Recommend only with clear safety language. 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)

Reynolds Wrap Everyday Strength Aluminum Foil Roll, Freezer and Grill Safe, Great for Foil Packets and Home Cooking, 12 Inches Wide, 200 Total Sq. Ft.

aluminum foilfabrication

Reynolds Wrap Everyday Strength Aluminum Foil Roll, 12 Inches Wide, 200 Total Sq. Ft.

$13.494.8(29K)

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)

MAGID Rubber Insulating Electrical Safety Gloves, Class 0 ASTM Compliant

glovessafety

MAGID Rubber Insulating Electrical Safety Gloves, Class 0 ASTM Compliant

4.5(955)

Safety-critical: verify voltage class and standards before recommending for high-voltage work.

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.

Goupchn Universal P6100 Oscilloscope Clip Probes 100MHz with Accessories Kit 1X 10X 2 Pack

test probes / leadstest equipment

Goupchn Universal P6100 Oscilloscope Clip Probes, 100MHz, 1X/10X, 2 Pack

$13.994.7(126)

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)

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.

Weliu Transparency Film Sheets for Inkjet Printers 30 Sheets, 100% Clear Paper Acetate Sheets for Overhead Projector 8.5 X 11 Inches

acetate / transparency filmfabrication

WeLiu Transparency Film Sheets for Inkjet Printers

$6.994.5(2,400)

3M Scotch Vinyl Electrical Tape Super 88, 3/4 in x 44 ft, Black, 1 roll, Premium Grade, Rubber Resin Adhesive, PVC Backing, A

electrical tapefabrication

3M Scotch Super 33+ Vinyl Electrical Tape

$4.534.8(2,814)

Project files

Prints, kits, and downloads.

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

Coming soon

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