Rationalised 2023-24
259
Wave Optics
In order to determine the shape of the refracted
wavefront, we draw a sphere of radius v2t from the point
A in the second medium (the speed of the wave in the
second medium is v2) Let CE represent a tangent plane
drawn from the point C on to the sphere Then, AE = v2 t
and CE would represent the refracted wavefront If we
now consider the triangles ABC and AEC, we readily
obtain
sin i = 
1
BC
AC
AC
=v τ
(10