Find two flat glass plates (microscope slides will work nicely). Wipe the glass plates clean and place one on top of the other. View the plates in reflected light from the overhead lighting in your room.
a. Describe the pattern of light and dark fringes that you see. Are there any colors associated with these fringes?
b. Place a very thin object such as a human hair between the two plates near one end. Does this change the fringe pattern? Can you explain the pattern that you see?