Question

What difference do you notice in refracted rays in 4 (c) and 4 (d)? What could be the reasons for that difference? 

(OR) 

Draw the ray diagrams when the incident ray passes through the curved surfaces. 

a) Rarer medium to denser medium.

b) Denser medium to rarer medium.

Answer 1

• In figure 4 (c) a ray travelling parallel to the principal axis strikes a concave surface and passes from a denser medium to a rarer medium. 
• In figure 4 (d) a ray travelling parallel to the principal axis strikes a concave surface and passes from a rarer medium to a denser medium. 

Reasons : 

• Figure 4 (c) :The refracted ray reaches a particular point on the principal axis.
• Figure 4 (d) : The refracted ray moves away from the principal axis. 
• The main reason is that light passes through different media.