In Youngs double slit experiment, the slit width and the distance of slits from the screen both are doubled. The fringe width:

Question

In Youngs double slit experiment, the slit width and the distance of slits from the screen both are doubled. The fringe width: (A) increases (B) decreases (C) remains unchanged (D) none of the above

Tardigrade Admin · Accepted Answer

Distance between two adjacent bright (or dark) fringes is called the fringe width. It is denoted by

β,

thus,

β = \frac{D λ}{d}

where D is the distance between slit source and screen and d is separation of slits. Since, D and d are increased to same extent, so fringe width (w) will remain unchanged.

Q. In Youngs double slit experiment, the slit width and the distance of slits from the screen both are doubled. The fringe width:

increases

decreases

remains unchanged

none of the above

Distance between two adjacent bright (or dark) fringes is called the fringe width. It is denoted by β, thus, β=dDλ​ where D is the distance between slit source and screen and d is separation of slits. Since, D and d are increased to same extent, so fringe width (w) will remain unchanged.