What fret is A# on the 2nd string?

The note A# is located on the 2nd string (B string) of the guitar. To find this note, you need to know the notes that correspond to each fret on this string. The open string is B. Moving up one fret takes you to C, up another fret to C#, and then up another fret to D. Continuing to the 4th fret, you find D#.

This sequence shows that after D on the 3rd fret, the next fret (4th) corresponds to D#. However, since A# is not found on the 2nd string, it will actually correspond to the 1st fret of the 2nd string which is B.

In summary, A# is achieved by playing on the 1st fret of the 2nd string, which keeps the musical hierarchy and fretboard structure in mind as you practice notes across different strings.