Why does energy depend on V squared?

Each incremental charge requires more work as the voltage across the capacitor increases, leading to the V^2 relationship.

Can capacitors replace batteries?

Supercapacitors can for short-term storage but have much lower energy density than batteries.

Is this energy dangerous?

Even small capacitors at high voltage can deliver a painful or dangerous shock. Always discharge before handling.

Capacitor Energy Calculator

Calculate the energy stored in a capacitor from capacitance and voltage.

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Capacitance

µF

Voltage

Stored Energy

0.3125 J

Stored Energy (mJ)312.50 mJ

Stored Energy vs Capacitance

View formula & how it works →

Capacitor Energy Storage

E = 0.5 x C x V^2

Energy scales with the square of voltage, so doubling voltage quadruples energy.

Example Calculation

1000 uF capacitor at 25 V.

01C = 1000 uF = 0.001 F
02E = 0.5 x 0.001 x 25^2 = 0.5 x 0.001 x 625 = 0.3125 J

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Ohm's Law Guide

A complete guide to Ohm's Law. Learn the relationship between voltage, current, and resistance, with practical examples, the power triangle, and circuit analysis tips.

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