Answer:
Change in the speed of light when it travels from one medium to other medium then due to this there is change in the path of light, this phenomenon is known as refraction of light.
Step-by-step explanation:
As we know that when moves from medium to other medium the speed of the light will change.
here we can find the speed of light by the formula

here we know that
= refractive index
now we know by Snell's law that when light incident at some angle on the interface of two mediums then it will be refracted at some other angle on the other medium. This is given by

so the change in angle is given as
