Through which of the following points will a ray passing through the centre of curvature and reflected by a concave mirror pass?

When does Snell's law fail?

Define the term reflection.

$(a)$ Draw a ray diagram in each of the following cases to show the position and nature of the image formed when an object is placed:
$(i)$ Between the focus and the centre of curvature of a concave mirror.
$(ii)$ Between the focus and the pole of a concave mirror.
$(iii)$ Between the centre of curvature and infinity for a concave mirror.
$(b)$ Give mathematical formulae for determining the magnification produced by a spherical mirror. What does $m = -1$ signify? Identify the mirror that can produce it.

What is the wavelength range of visible light in $cm$?

Why does a light ray incident on a rectangular glass slab immersed in any medium emerge parallel to itself? Explain.