AIIMS 2018 May 26 Physics Morning Question Paper with solutions for online practice

In the figure shown S is the source of white light kept at a distance x0 from the plane of the slits. The source moves with a constant speed u towards the slits on the line perpendicular to the plane of the slits and passing through the slit S1 . Find the instanteneous velocity (magnitude and direction) of the central maxima at time t having range 0≤t<<

x0−d

u

. Assume that D >> d.