Ans given 3
I am getting 4
VEDANT ZOPE last edited by VEDANT ZOPE
The slab if of thickness d and slit is of thickness t so answer is correct you have assumed slab thickness to be t
Optical path difference at
P = S2P - [S1P+ µt - t]
= S2P - S1P - (µ - 1)t
= y.d/D - (µ - 1)t=0 for lateral shift.
y= (µ - 1)tD/d
I have taken thickness as t and distance between slits as d.
But in your question its reverse, thickness as d and distance as t.. so ans is 3