Question

In a two-slit experiment with white light, a white fringe is observed on a scren kept behind the slits. When the screen is moved away by $0.50m$, this white fringe

• A. does not move at all
• B. gets displaced from its earlier position
• C. becomes colored
• D. diappears

Answer 1

The correct option is A does not move at all

White slit is obtained at the central maxima of the interference pattern, which is at a point on the screen to which a line passing through mid point of the slits, perpendicular to the screen meets the screen. Even by moving the screen away or towards the slits, central maxima is still obtained at the same point.