Power chords get their name because they provide support because you can play the root and the fifth of a chord, giving it a wider sound and a stronger bass. Power chords can also be used in minor and major contexts because there's no third, so it's just an open fifth sound. You get the sound of a power chord by playing any note, and then playing the fifth from that note which is, on a bass, often one string up and two frets over. This power chord sound can then be applied and moved in the same shape anywhere on the instrument you want to. If you're playing an open string, you can get the power chord sound by playing the second fret of the string right above it. Here's some examples of playing power chords. A variation you can play with power chords is to add the octave of your root note. If you're gonna play an E power chord with the root on top, you can play an E as the seventh fret, and the A string. The fifth, B, which is the ninth fret on the D string, and then the E again - that's the 9th fret on the G. So sometimes this can be an even stronger sound to use if you want a full chord sound imitating a bar chord sound on a guitar. And that's how to play power chords on the bass.