2. (a)
A convex spherical surface of radius +50 mm separates air fromglass of refractive index 1.6. A parallel pencil of rays in air isincident on this surface. Find where the refracted pencil comes toa focus in the glass.
(b) Where must a point object be placed in air to make therefracted pencil parallel?
(c) Repeat (a), assuming the incident pencil to be diverging from apoint in air 50 cm from the surface.
(d) Repeat (a), assuming the incident pencil to be converging to apoint inside the glass 50 mm from the surface.
(e) Repeat (a), assuming the incident pencil to be converging to apoint inside the glass 20 mm from the surface (Bennett, chapter 2,question 4).
Can you please explain on sign convention in the answer?
