College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 48

Interference effects are produced at point P on a screen as a result of direct rays from a 500-nm source and reflected rays offa mirror, as shown in Figure P24.67. If the source is L = 100 m to the left of the screen and h = 1.00 cm above the mirror, find the distance y (in millimeters) to the first dark band above the mirror.