As intensity is maximum at axis, ∴μ will be maximum and speed will be minimum on the axis of the beam. ∴ beam will converge.
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. As the beam enters the medium, it will
Held on 30 Apr 2010 · Verified 6 Jul 2026.
diverge
converge
diverge near the axis and converge near the periphery
travel as a cylindrical beam
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