Understanding Capacitors

In this exercise, we consider capacitors as "buckets of charge". The most common polarized capacitor is the electrolytic capacitor (elko). For elkos, the longer leg is positive (+) and the shorter leg is negative (-). This polarity is especially important when dealing with higher voltages, as incorrect connection can cause the capacitor to explode or leak.

Capacitors are used for various purposes including energy storage, filtering, timing circuits, and coupling/decoupling signals.

LED Capacitor Circuit

Try this in your breadboard and see how it corresponds to the calculator at the end of this page

To Do and Not To Do

Different Types of Caps

More Capacitor Types Capacitor Types More Capacitor Types

Additional Resources

For more detailed information about capacitors, visit:

Electronics Tutorials - Capacitors

Watch an educational video about capacitors:

YouTube - Understanding Capacitors

Learn more about capacitor types:

DigiKey - Types of Capacitors

Charge Calculator (Coulombs)

Calculate the charge (Q) stored in a capacitor:

Time Constant Calculator

Calculate the time constant (τ) of an RC circuit:

LED Time Calculator

Calculate how long the LED will stay lit: