Using a Capo

This is a 1.8333 minute video response from DJ Phillips on Sep 15th, 2009

Question:

"If I am playing a chord progression in the key of G and a 2nd guitar is playing a lead line using the Em pentatonic scale, what happens if a capo is put on the 7th fret of the second guitar. Does the lead guitar now play in the Am pattern? A capo on the 7th fret with a C chord pattern produces a G chord sound; so do you use a Am pattern (relative minor of C) to get the sound of Em pentatonic scale. I hope this isn't confusing."