The diagram alongside shows a lens as a combination of a glass slab and two prisms.
(i) Name the lens formed by the combination.
(ii) What is the line XX' called ?
(iii) Complete the path of the incident ray AB after passing through the lens.
(iv) The final emergent ray either meets XX' at a point or apppears to come from a point on XX'. Label it as F. What is this point called ?
(i) The combination forms a concave lens.
(ii) XX' is known as the principal axis.
(iii)
(iv) The point F is called the second focus.