JEE Advanced Model Paper 16 with solutions for online practice

A monochromatic beam of electrons accelerated by a potential difference V fallsnormally on the plane containing two narrow slits separated by a distance d. Theinterference pattern is observed on a screen parallel to the plane of the slits and at adistance of D from the slits. Fringe width is found to be w1 . When electron beam isaccelerated by the potential difference 4V the fringe width becomes w2. Find theratio

w1

w2

. (Given d ≪ D)