Question:
Beams of light are incident through the holes A and B and emerge out of a box through the holes C and D respectively as shown in figure. Which of the following could be inside the box ?
(a) A rectangular glass slab
(b) A convex lens
(c) A concave lens
(d) A prism.
Solution:
(a).
Explanation : Rectangular glass slab causes the lateral dis¬placement of a ray of light following on it. However, incident ray and emergent ray are
paralled to each other.