In a Young’s double-slit experiment, the two slits behave as coherent sources.
When coherent light waves superpose over each other they create an interference pattern of
successive bright and dark regions due to constructive and destructive interference.
Two slits 2 mm apart are illuminated by a source of monochromatic light and the interfer-
ence pattern is observed on a screen 5.0 m away from the slits as shown in the figure.
