Question

any 2 condition of refraction

Answer 1

The same two conditions that are necessary for bending the path of the line of students are also necessary for bending the direction of a light ray. Light refracts at a boundary because of a change in speed. ... The change in speed is the cause and the change in direction (refraction) is the effect.

Answer 2

Two necessary conditions for refraction are as follows :

a. change in medium , either medium change is from denser to rarer or from rarer to denser.
b. Change in speed of light, leads to bending of light rays during change in medium.