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Electricity

Solar panel made of LEDs

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

ElectricityBuildElectronics

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How it works

What this project is testing.

An LED can work in reverse. Usually electricity goes in and light comes out; shine enough light on the junction and it can produce a small voltage and current.

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This experiment demonstrates the photovoltaic effect and the tradeoff between voltage and current when LEDs are arranged together.

E_{γ} = \frac{h c}{λ}

Shorter-wavelength light carries more energy per photon, which matters for freeing charge in a junction.

P = I V

The useful electrical power is voltage times current, usually tiny for LEDs used this way.

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.

Amazon Basics 8-Pack 9V Long-Lasting Alkaline Batteries for Smoke Detector, Electronics & Audio, Reliable, 5-Year Shelf Life

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General electronics battery pick; choose AA/AAA variants when the circuit calls for them.

Auto Ranging Digital Multimeter TRMS 6000 with Battery Alligator Clips Test Leads AC/DC Voltage/Account,Voltage Alert, Amp/Ohm/Volt Multi Tester/Diode

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

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

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SUNYIMA 10pcs Mini Monocrystalline Solar Cells Solar System Kit 50mm X 50mm/1.96" X 1.96" 2V 160MA for DIY Charge Solar Panels

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BOJACK 1000 Pcs 25 Values Resistor Kit 1 Ohm-1M Ohm with 5% 1/4W Carbon Film Resistors Assortment

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BOJACK 3 Values 130 Pcs Solderless Breadboard 4 Pcs 830 Tie Points & 400 Tie Points & 126 Pcs Flexible Breadboard Jumper Wires

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Tolako 5v Relay Module 5V Indicator Light LED 1 Channel Relay Module for Arduino ARM PIC AVR MCU

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Swpeet 32Pcs 7 Sizes Clip-on Ferrite Ring Core with Toroid Core Assortment Kit, RFI EMI Noise Suppressor Cable Clip for 3.5/5/7/9/13/15/42 * 24 * 16mm Diameter HDMI USB Cable

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

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