Refraction, Glass Slab & Apparent Depth
An initially parallel cylindrical beam travels in a medium of refractive index where and are positive constants and 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
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Answer: (b)
- Intensity is maximum on the axis, so is maximum on the axis and decreases outward.
- Light is slower near the axis, so the wavefront lags at the centre and becomes concave in the direction of travel.
- Rays bend towards the region of higher , i.e. towards the axis (like a graded-index lens).
- So the answer is (b) converge.