Question
An initially parallel cylindrical beam travels in a medium of refractive index μ(I) = μ0 +μ2I , where μ0 and μ2 are positive constants and I is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius.
The initial shape of the wavefront of the beam is
-
convex
-
concave
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convex near the axis and concave near the periphery
-
Planar
Solution
D.
Planar
For a parallel cylindrical beam, wave length will be planar.
