Today I was looking at David Bowie’s ‘Space Oddity’ and in particular the question of which shape to use for a C/G chord. This is a second inversion, the type of chord where the 5th is the lowest note rather than the root note or the 3rd. In traditional music harmony there are many rules about the use of second inversions; how they are approached and how quitted. Guitarists tend not to be much bothered about the special identity of second inversion chords. Instead, they tend to use them as a means to have more strings sounding.
Here’s an example. An open C chord in first position is usually played x32010. If it is turned into a second inversion – 332010 – the 6th string can be played. Bowie seems to have been fond of this way of playing a C in songs like ‘Queen Bitch’ and I think it was for the extra resonance. But it isn’t functioning as a second inversion, just a more resonant C chord.
For a C/G that sounds like a second inversion, especially in a sequence where the bass note was at A and is falling to F# or F, I recommend 3×2010. It’s a subtle difference, but the removal of the low root note makes the second inversion stand out with more of an identity.