you’re playing a F# major chord, because your lowest note (the root note) is now on the sixth string, second fret, which is an F# note. If you don’t know all the notes on the strings check out“Learn the guitar fingerboard thoroughly in 16 days”. ...
But let’s reverse that train of thought for a moment. The notes of an A chord are A, C# and E. We can check that out by comparing this chord chart of the open position A and see that the open high E (first string) is E, the second fret of the B string is C#, the second ...