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The optical phenomena taking place for a mirror and for a lens respectively are ______ and ______.

Asked in GSEB Board March 2023 · Plane mirrors

Answer: (3) reflection, refraction

Step-by-step solution

Given: a mirror and a lens.

Idea: ask what the light does at the surface in each case.

At a mirror the light never enters the material: it turns back into the medium it came from, obeying the law of reflection, angle of incidence equal to angle of reflection.

At a lens the light crosses into the glass and out again, changing direction at each surface because its speed changes -- that is refraction, governed by Snell's law.

Interference and diffraction are wave effects needing coherent sources or narrow apertures; they are not how everyday mirrors and lenses build images.

So the phenomena are reflection for the mirror and refraction for the lens.

Why the other options are wrong

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